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rjracin240
09-12-2011, 07:37 AM
Look for some advice to try tonight.

Here is the scenario:

The boat had been running great all summer, ran the boat several weekends ago and then took off for Iowa to drop my daughter off in school the following weekend. Came back and ran the boat the following weekend (just about two weeks of not running the boat). When running the boat, the boat would run up to WOT and then fall flat on its face. Diagnosed it as a fuel flow problem, so pulled the filter bowl and found some water in the bowl. drained water and then put it back together with the result of boat running up to WOT and maintaining it. New problem is it detonates/preignition when dumpping the throttle. If you slowly accelarate up to 2,000RPM there is no issue, however if you pass 2,000RPM then you have quite a bit of detonation. Might be my imagination, but seems more predominate on the STBD side.

Checked timing and have 10BTDC @ 600RPM in gear. Drained fuel tank completely and put in fresh 89 octane fuel. Checked all plug wires to insure they were seated in distributor and on plugs.

Was going to run boat tonight and run engine up past 2,000rpm and try and see what total advance is, as it seems to me that I have some sort of issue with distributor advance.

One friend said that he thinks for some reason I am going lean on the top end and this is causing the detonation. I know earlier in the year I was having some issues with detonation when I had the automotive carburettor from the previous owner. Once I put the new Holley on that problem went away. if there is a problem where something on the carb got plugged up, where on the carb would I look?

Any other suggestions would be appreciated.


1988 Prostar 190 with 351 and electronic ignition conversion

1redTA
09-12-2011, 07:51 AM
put some 93 in it and see if the detonation goes away. I would also run some seafoam thru it

tommcat
09-12-2011, 08:45 AM
do you know for sure it's deto that you're hearing? are there any signs of it on the plugs, how do they look? do they look lean?

rjracin240
09-12-2011, 09:43 AM
do you know for sure it's deto that you're hearing? are there any signs of it on the plugs, how do they look? do they look lean?

Pretty sure it is detonation, admit I grasped at some straws and replaced the exhaust manifold gaskets as they looked blown out at the bottoms of the exhaust ports. Thought I was mistaking exhaust leak for detonation. Not the case! Will pull plugs and see if they are lean, hate to think I need to go into a brand new carb.

JimN
09-12-2011, 09:52 AM
Pretty sure it is detonation, admit I grasped at some straws and replaced the exhaust manifold gaskets as they looked blown out at the bottoms of the exhaust ports. Thought I was mistaking exhaust leak for detonation. Not the case! Will pull plugs and see if they are lean, hate to think I need to go into a brand new carb.

Check your timing at higher speeds. If it's advanced too much, you'll see it. If you don't, all you can do is guess. You didn't mention checking the centrifugal advance weights & springs- do that, too. You might have a broken spring, or two.

tommcat
09-12-2011, 09:55 AM
Pretty sure it is detonation, admit I grasped at some straws and replaced the exhaust manifold gaskets as they looked blown out at the bottoms of the exhaust ports. Thought I was mistaking exhaust leak for detonation. Not the case! Will pull plugs and see if they are lean, hate to think I need to go into a brand new carb.rejetting a carb is no big deal and you really cant expect one to be correct out of the box. jetting realistically could be adjusted several times from spring to fall just due to the temp changes. altitude and temp have quite an effect on jetting.

only a few causes for deto if that's actually the case. lean fuel mixture, too much timing at any given rpm or some hot spot in the combustion chamber such as a sharp valve edge or carbon build up. check fuel first since you did just do carb work.

tommcat
09-12-2011, 09:57 AM
Check your timing at higher speeds. If it's advanced too much, you'll see it. If you don't, all you can do is guess. You didn't mention checking the centrifugal advance weights & springs- do that, too. You might have a broken spring, or two.question for you on that part jim, in a boat do you usually set the springs to have advance come in real early? what rpm do you try to get full advance in by?

east tx skier
09-12-2011, 10:04 AM
Are all of your plug boots tight?

oldairboater
09-12-2011, 01:48 PM
Carburetors don't like water sitting in them. Where did the water come from in the fuel and did you get all of it out? Check timing first. Like listed above check all of the plugs. Look at or replace wires. Check weights and springs in distributor. Look at cap and rotor. If all that looks good then pull carb and go through it. You don't need a new carb---you may need to rebuild or clean your carb.

rjracin240
10-17-2011, 11:58 AM
Finally got a chance to do some extensive troubleshooting while having a friend drive the boat. Drove the boat at about 2,500 while pouring some water down the carb (I can hear the groans now!) to decarbonize the engine, no luck still detonating. Double checked the timing again, set the mixture and and adjusted idle, still detonating. Then started looking and listening to engine to see if the detonating could be isolated. Found water spurting out of #1 cylinder head lower bolt and a little out between the head and block. The water spurting out of the head bolt was hitting the back of the alternator and was making a sound like detonating. My friend helping me out had his son with him so had him torque the head. in retrospect should have done it myself. Dont have a Indmar manual so use the PCM manual dowloaded from this site. Torque value for the cylinder head bolts was listed as being step torqued @ 90-100-112 So when he went to 100FTLBs the bolt snapped. Thinking if it was me would have felt bolt stretch and would have known to back it off. Valuable lesson for both him to know what stretch feels like before letting loose and for me not to have done this crucial step myself. Also has me curious as to wether the torque I got out of the manual is correct. Standard torque table for a 1/2-13 bolt was no more than 60ftlbs, with a note saying that if other secific torque was specified to use that!

Hoping that I can easy out the bolt left in the block by using a left hand bit and lots of penetrating oil and prayers!

Not sure if this is a common problem for the head bolt on #1 to loosen like that. Engine had steady vacuum at 15 with no oscillation so thinking the head gasket sealing #1 cylinder is intact.

Any suggestions or comments welcome

1redTA
10-17-2011, 12:33 PM
some engines use torque to yield bolts that are supposed to be one time use. good luck getting it out I would get the bolt warmed up when you do it

JimN
10-17-2011, 01:43 PM
Finally got a chance to do some extensive troubleshooting while having a friend drive the boat. Drove the boat at about 2,500 while pouring some water down the carb (I can hear the groans now!) to decarbonize the engine, no luck still detonating. Double checked the timing again, set the mixture and and adjusted idle, still detonating. Then started looking and listening to engine to see if the detonating could be isolated. Found water spurting out of #1 cylinder head lower bolt and a little out between the head and block. The water spurting out of the head bolt was hitting the back of the alternator and was making a sound like detonating. My friend helping me out had his son with him so had him torque the head. in retrospect should have done it myself. Dont have a Indmar manual so use the PCM manual dowloaded from this site. Torque value for the cylinder head bolts was listed as being step torqued @ 90-100-112 So when he went to 100FTLBs the bolt snapped. Thinking if it was me would have felt bolt stretch and would have known to back it off. Valuable lesson for both him to know what stretch feels like before letting loose and for me not to have done this crucial step myself. Also has me curious as to wether the torque I got out of the manual is correct. Standard torque table for a 1/2-13 bolt was no more than 60ftlbs, with a note saying that if other secific torque was specified to use that!

Hoping that I can easy out the bolt left in the block by using a left hand bit and lots of penetrating oil and prayers!

Not sure if this is a common problem for the head bolt on #1 to loosen like that. Engine had steady vacuum at 15 with no oscillation so thinking the head gasket sealing #1 cylinder is intact.

Any suggestions or comments welcome

At this point, I seriously doubt the bolts can still stretch and after being in place for so long, their elasticity is gone. Head bolts go through so many heat cycles and if the cooling system fails to do its job (for whatever reason, even if it's only once), they become "work-hardened". You'll need to drill that broken bolt out and it's not gonna be fun- I say this from first-hand experience. This one bolt is an indication and I would strongly advise against re-using any of the old head bolts when you re-assemble it. The torque of the bolts isn't even close to what it's supposed to be and I would have the heads checked for flatness. Have them shaved, if necesary.

JimN
10-17-2011, 01:45 PM
question for you on that part jim, in a boat do you usually set the springs to have advance come in real early? what rpm do you try to get full advance in by?

No- the advance needs to come in gradually- if the spark comes too early at mid-range RPM, detonation will occur. IIRC, max advance comes in at about 3K.

CantRepeat
10-17-2011, 01:58 PM
Finally got a chance to do some extensive troubleshooting while having a friend drive the boat. Drove the boat at about 2,500 while pouring some water down the carb (I can hear the groans now!) to decarbonize the engine, no luck still detonating. Double checked the timing again, set the mixture and and adjusted idle, still detonating. Then started looking and listening to engine to see if the detonating could be isolated. Found water spurting out of #1 cylinder head lower bolt and a little out between the head and block. The water spurting out of the head bolt was hitting the back of the alternator and was making a sound like detonating. My friend helping me out had his son with him so had him torque the head. in retrospect should have done it myself. Dont have a Indmar manual so use the PCM manual dowloaded from this site. Torque value for the cylinder head bolts was listed as being step torqued @ 90-100-112 So when he went to 100FTLBs the bolt snapped. Thinking if it was me would have felt bolt stretch and would have known to back it off. Valuable lesson for both him to know what stretch feels like before letting loose and for me not to have done this crucial step myself. Also has me curious as to wether the torque I got out of the manual is correct. Standard torque table for a 1/2-13 bolt was no more than 60ftlbs, with a note saying that if other secific torque was specified to use that!

Hoping that I can easy out the bolt left in the block by using a left hand bit and lots of penetrating oil and prayers!

Not sure if this is a common problem for the head bolt on #1 to loosen like that. Engine had steady vacuum at 15 with no oscillation so thinking the head gasket sealing #1 cylinder is intact.

Any suggestions or comments welcome

351w 55-65-95 on 1/2 bolts is what I see.

Kevin 89MC
10-17-2011, 05:00 PM
I'm pretty sure the Indmar service manual calls for stepped torque around the 90-100-112 values on my '89 351. The last value was a range IIRC, I just dialed the wrench in the middle of the range, but I'm fairly certain it was over 100. Bummer about the bolt, good luck extracting it.
Kevin

CantRepeat
10-17-2011, 05:07 PM
I'm pretty sure the Indmar service manual calls for stepped torque around the 90-100-112 values on my '89 351. The last value was a range IIRC, I just dialed the wrench in the middle of the range, but I'm fairly certain it was over 100. Bummer about the bolt, good luck extracting it.
Kevin

What I see is 90 - 100 so 95. There is no way the first torque on a head bolt with a final torque of 95 or 100 is going to 90.

rjracin240
10-18-2011, 07:31 AM
some engines use torque to yield bolts that are supposed to be one time use. good luck getting it out I would get the bolt warmed up when you do it

Know all about that one as the head bolts for the Datsun L series motors are the same way

No- the advance needs to come in gradually- if the spark comes too early at mid-range RPM, detonation will occur. IIRC, max advance comes in at about 3K.

While troubleshooting the perceived detonation, I was observing full advance of 20DBTDC @ 2,000 rpm, from my understanding of what you are saying; I am getting my advance to early. What would you say would be the max advance I should get. The springs in the distributor did look relatively loose in there but were intact and looked to be in good condition

351w 55-65-95 on 1/2 bolts is what I see.

Just curious to know where you got these numbers and whether these were the numbers for a 302 vs. a 351W. Have to admit I dont feel too comfortable with the numbers I was going by as they seem awfully high.

Havent worked with any American V8's before, any recommendations for head bolt's?

CantRepeat
10-18-2011, 07:54 AM
351w 1/2 thread head bolt Kit, . Part# 154-3603

There are few different sources for the head bolt torque but strangely enough I can not find the torque sequence but I'm sure it's center out.

http://www.classictruckshop.com/bt351W.php

There does seem to be references up to 105 lbs but a large number of googles point to 90/100. I'm sure new bolts would not snap at the higher number.

JimN
10-18-2011, 08:40 AM
While troubleshooting the perceived detonation, I was observing full advance of 20DBTDC @ 2,000 rpm, from my understanding of what you are saying; I am getting my advance to early. What would you say would be the max advance I should get. The springs in the distributor did look relatively loose in there but were intact and looked to be in good condition

Just curious to know where you got these numbers and whether these were the numbers for a 302 vs. a 351W. Have to admit I dont feel too comfortable with the numbers I was going by as they seem awfully high.

Havent worked with any American V8's before, any recommendations for head bolt's?

I was ball-parking the advance- a service manual would be a better source for this AND the torque specs.

95 ft-lb for 1/2" bolts for heads sounds a little low unless the engine is low compression. 100-110ft-lb is common but, as I posted, work-hardened bolts are brittle and don't stretch at all. Also, even if the bolts have been in place for a long time, they need to be loosened before torquing. If there's any rust on the shoulder, there's probably rust on the shank and thread, so any theoretical torque setting on the wrench isn't going to be what's delivered to the head of the bolt because the rest of it isn't moving.

CantRepeat
10-18-2011, 09:09 AM
I was ball-parking the advance- a service manual would be a better source for this AND the torque specs.

95 ft-lb for 1/2" bolts for heads sounds a little low unless the engine is low compression. 100-110ft-lb is common but, as I posted, work-hardened bolts are brittle and don't stretch at all. Also, even if the bolts have been in place for a long time, they need to be loosened before torquing. If there's any rust on the shoulder, there's probably rust on the shank and thread, so any theoretical torque setting on the wrench isn't going to be what's delivered to the head of the bolt because the rest of it isn't moving.

I did read a couple of post that said there were different numbers for head torque between the Chilton and Hayes books.

Kevin 89MC
10-18-2011, 09:19 AM
I just checked my Indmar service manual. For the 1989 351, the bolts are to be torqued in 3 steps. First pass is 85, 2nd pass is 95, then final pass is 105-112. I set the torque wrench at 109 for my final pass. The manual also has the specs for the 302 block, torque is a bit different for that. Only 2 passes, first at 55-65, final pass at 65-72. I would strongly recommend getting the Indmar service manual if you are digging into the engine. I would recommend ARP head bolts, got mine from Summit Racing. Came with the proper lube, and a sticker for a few more HP. ;)
Good luck,
Kevin

JimN
10-18-2011, 10:20 AM
I did read a couple of post that said there were different numbers for head torque between the Chilton and Hayes books.

With all due respect to Haynes and Chilton's, they didn't build the engine, nor did they do the testing when the engine was developed so I tend to trust a manufacturer's manual before a third-party manual unless the third party got the info directly from the manufacturer or developer and, since there's a difference between the torque specs from these manuals, it's impossible to really trust both, or either, when the OEM specs haven't been seen.

I have, however, seen FelPro torque patterns and specs that coincided with OEM service manuals and I used them with success on at least one 351 engine after a partial or total tear-down.

An engine from '89 was probably not designed with 'torque to yield' or 'torque angle' fasteners, so I wouldn't worry about that. It's cast iron, not aluminum and therefore, it's less of an issue if the head bolts are at 100 or 105 ft-lb. Neither is excessive or insufficient to hold a head down well enough for long-term use without failure.

JimN
10-18-2011, 10:25 AM
I just checked my Indmar service manual. For the 1989 351, the bolts are to be torqued in 3 steps. First pass is 85, 2nd pass is 95, then final pass is 105-112. I set the torque wrench at 109 for my final pass. The manual also has the specs for the 302 block, torque is a bit different for that. Only 2 passes, first at 55-65, final pass at 65-72. I would strongly recommend getting the Indmar service manual if you are digging into the engine. I would recommend ARP head bolts, got mine from Summit Racing. Came with the proper lube, and a sticker for a few more HP. ;)
Good luck,
Kevin

Did you get the 5HP or 10HP sticker?:D

Kyle
10-18-2011, 11:25 AM
Is there any chance that you can remove the head and grab the bolt with vise grips.

Did it break off in the block where the threads are?

I think the head gasket needs to be replaced anyway. I would remove the heads. Fix the broken bolt. Have heads inspected by a machine shop. Replace both head gaskets and a new set of head bolts. My 2 cents.

thatsmrmastercraft
10-18-2011, 11:26 AM
^^^Ditto^^^

Kyle
10-18-2011, 11:28 AM
Post a pic of this broken bolt.

rjracin240
10-18-2011, 11:45 AM
Post a pic of this broken bolt.

As requested if you look at the top of the bolt it looks already broken, wish I had done the torqueing so I could have had a better feel of what was going on with bolt. From my observation of my friends son it did look like he was getting some torque on the bolt.

CantRepeat
10-18-2011, 11:48 AM
Kyle!! Your famous now!! You too Peter!

thatsmrmastercraft
10-18-2011, 12:00 PM
Kyle!! Your famous now!! You too Peter!

Famous of infamous?:rolleyes:

thatsmrmastercraft
10-18-2011, 12:03 PM
As requested if you look at the top of the bolt it looks already broken, wish I had done the torqueing so I could have had a better feel of what was going on with bolt. From my observation of my friends son it did look like he was getting some torque on the bolt.

Is that little shiny part the part that broke and all the rest is rusted?

rjracin240
10-18-2011, 12:10 PM
Is that little shiny part the part that broke and all the rest is rusted?

True observation, the shiny witness mark must have wedged itself in there and allowed some torque to be put on the bolt before shearing. The kid said that the bolt was hand tight, bumming I did not feel it before it we started tightening it!

thatsmrmastercraft
10-18-2011, 12:15 PM
It sure looks like that bolt had already cracked some time ago, and the torque just snapped what was left. If that is the case, getting the old bolt remains out of the block may not be all that difficult.

Kyle
10-18-2011, 12:16 PM
Ok now we are getting somewhere. You broke a bottom head bold not the bolt that runs down through the head under the valve covers.

I would be extremely careful drilling and using an easy out. If you snap the easy out off down there you will be Screwed Hard and your boat will have about 25 new names. Head bolts stay pretty tight or snug most of the way out.

I would remove the head first. You need a new gasket anyway so just take the heads off. Then take the heads to a machine shop to get checked along with the boat. Have the machine shop look at the block. They have all kinds of tools to get it out. He may recommend a heli coil if the threads get screwed up by a drill bit. They get broken off bolts all of the time. Get a second opinion before drilling inti a block.

Kyle
10-18-2011, 12:33 PM
Looking at the bolt it looks to be sheared off pretty flush with the block. The block has about a 1/4" space from the top of the block and where the threads begin in that hole.

Since the bolt was broken by tightening then it's not going to be a cake walk most likely. Is it cross threaded. Was the bolt old. What is in the block is tighter than a drum.


You say "Kid". How old or knowledgable was this "Kid". Head bolts strip easier than snap. Are you sure he didn't have the torque wrench set at 200 instead of 100. This is weird.

rjracin240
10-18-2011, 01:27 PM
Looking at the bolt it looks to be sheared off pretty flush with the block. The block has about a 1/4" space from the top of the block and where the threads begin in that hole.

Since the bolt was broken by tightening then it's not going to be a cake walk most likely. Is it cross threaded. Was the bolt old. What is in the block is tighter than a drum.


You say "Kid". How old or knowledgable was this "Kid". Head bolts strip easier than snap. Are you sure he didn't have the torque wrench set at 200 instead of 100. This is weird.

He is 15 years old, his Dad keep's him pretty active doing mechanical stuff so he isnt a gameboy moron kid that has no common sense! (hope I dont get flamed for that Characterization!) torque wrench was set at 100.
Coming to the realization that I need to pull the boat out and start getting busy on pulling heads etc unfortunately looking at a bad headgasket no matter how I look at it.

Sucks already have my Z Car I have to put a engine in from a failure at a track day earlier this summer!

Thanks everyone for your inputs, interests, and suggestions. Will keep you all posted as the inevitable progresses with pictures and narration.

Kyle
10-19-2011, 12:58 AM
If you wanna look at the water Jackets look here and you can see how the backside of the head is.

http://www.mastercraft.com/teamtalk/showthread.php?t=44156

Kyle
10-19-2011, 01:03 AM
Here is the water jackets for the block.

http://www.mastercraft.com/teamtalk/showthread.php?t=36324&page=10


You may have to scroll up or down so see pics.

JLeuck64
10-19-2011, 01:32 AM
OMG... I can't take it any more! It's been a fun ride guys but I am outta here.. take care
JLeuck64

thatsmrmastercraft
10-19-2011, 09:40 AM
OMG... I can't take it any more! It's been a fun ride guys but I am outta here.. take care
JLeuck64

What's wrong with a little obsessive/compulsive MC behavior?:confused::D

Kyle
10-19-2011, 11:31 AM
OMG... I can't take it any more! It's been a fun ride guys but I am outta here.. take care
JLeuck64

No your not..........

You will be back and we all will see ya then.

1redTA
10-19-2011, 01:09 PM
take a nut and weld it to the top of the bolt, they usually come out pretty easy after some good heat

riggsy3
10-20-2011, 08:02 AM
It's interesting to me there doesn't seem to be an agreement on the torque values for 351w head bolts (1/2 inch). After some online research on "torque" there are several factors to consider: the age and condition of the bolt (spend the $70 and get new bolts), bolt thread friction (use a tap to clean out bolt holes in block), the difference in the clamping pressure between the head and block is significant if you lubricate the thread and/or under the bolt head or not. Example: if you torque the head bolts to 100 ft.lbs. without lubricating bolts your torque wrench will hit 100 in less turns of the bolthead than if the bolts were lubricated which means the head is not as "tight" to the block.

Check out this one website on torque. Yes, your head will spin with all the technical jargon but I think you'll get the picture. http://www.pcbloadtorque.com/pdfs/technicalArticles/FundamentalsOfTorqueTension.pdf

thatsmrmastercraft
10-20-2011, 10:03 AM
It's interesting to me there doesn't seem to be an agreement on the torque values for 351w head bolts (1/2 inch). After some online research on "torque" there are several factors to consider: the age and condition of the bolt (spend the $70 and get new bolts), bolt thread friction (use a tap to clean out bolt holes in block), the difference in the clamping pressure between the head and block is significant if you lubricate the thread and/or under the bolt head or not. Example: if you torque the head bolts to 100 ft.lbs. without lubricating bolts your torque wrench will hit 100 in less turns of the bolthead than if the bolts were lubricated which means the head is not as "tight" to the block.

Check out this one website on torque. Yes, your head will spin with all the technical jargon but I think you'll get the picture. http://www.pcbloadtorque.com/pdfs/technicalArticles/FundamentalsOfTorqueTension.pdf

All very good points.

Kevin 89MC
10-20-2011, 10:06 AM
Yeah, if you think there are different interpretations of the proper torque for the 351, take a look at the 1986.5-1992 Toyota Supra Turbo's sometime. It was never officially acknowledged by Toyota, but the one big fault of the design most people think was headbolt torque. The rest of the engine & drivetrain is quite bulletproof, lots of folks run 400+ HP with no other major issues on mostly stock parts. Factory torque was something like 58 IIRC, and on a turbocharged inline 6, iron block & aluminum heads, headgaskets blew quite frequently. Most folks torque around 100 with new ARP bolts or studs, but it is different depending on what is used for bolt lube.
This is probably the only time I ever vary from the manufacaturer's recommendation. I trust the Indmar manual more than I trust Chiloton's, Haynes, the internet, etc. I figure Indmar knows much more about Ford's block as it is used in the marine environment than anyone else.
Kevin

JimN
10-20-2011, 10:23 AM
AFAIK. Indmar and MC don't put the heads on the blocks, GM does. Because of that, I'm pretty sure they get the torque specs from GM or, when applicable, Ford.

If lube is actually called for, and that's not always the case, the bolt selection makes a difference. If lube is used on a bolt with a low yield point, the bolt can break when it's needed most. Bolts use the shoulder and the thread to draw the parts together but it's the metal stretching that keeps the two in firm contact. If the torque is inadequate, the bolt can stretch when it shouldn't and the gasket will fail.

thatsmrmastercraft
10-20-2011, 10:25 AM
Yeah, if you think there are different interpretations of the proper torque for the 351, take a look at the 1986.5-1992 Toyota Supra Turbo's sometime. It was never officially acknowledged by Toyota, but the one big fault of the design most people think was headbolt torque. The rest of the engine & drivetrain is quite bulletproof, lots of folks run 400+ HP with no other major issues on mostly stock parts. Factory torque was something like 58 IIRC, and on a turbocharged inline 6, iron block & aluminum heads, headgaskets blew quite frequently. Most folks torque around 100 with new ARP bolts or studs, but it is different depending on what is used for bolt lube.
This is probably the only time I ever vary from the manufacaturer's recommendation. I trust the Indmar manual more than I trust Chiloton's, Haynes, the internet, etc. I figure Indmar knows much more about Ford's block as it is used in the marine environment than anyone else.
Kevin

A definite must as all the older torque specs are for dry, clean (new) bolts and bolt holes tapped and cleaned.

The other extreme is aluminum wheels with aluminum lug face. Correct torque is approx. 85 - 100 ft. pounds. Most are torqued to 150 or so - whatever the impact is set at. People typically think their capabilities are greater than they are.:confused:

Kevin 89MC
10-20-2011, 10:38 AM
I would have thought that Indmar/PCM would talk to the Ford/GM techs and possibly change some of the specifics on the block, like headgasket torque. But maybe not, it's just speculation on my part, I'm no expert that's for sure. Does anyone know what Ford specified the headbolt torque on their 1989 351 engines for their trucks & cars? I'd be curious to see if it is any different than what they recommended for the Indmar/PCM blocks, due to the different marine environment (different cooling, more constant high RPM's, etc). Chilton & Haynes manuals had to get their info somewhere. I think Toyota had different torque values based on whether the Supra came with a turbo, or not. Granted that is a bit different. Not trying to argue, just curious, always trying to learn something. And Jim you're right about the lube, if needed. That can make a huge difference. Another reason I stuck with a major manufacturer (ARP) and followed their installation instructions.

j.mccreight@hotmail.com
10-20-2011, 12:00 PM
I would have thought that Indmar/PCM would talk to the Ford/GM techs and possibly change some of the specifics on the block, like headgasket torque. But maybe not, it's just speculation on my part, I'm no expert that's for sure. Does anyone know what Ford specified the headbolt torque on their 1989 351 engines for their trucks & cars? I'd be curious to see if it is any different than what they recommended for the Indmar/PCM blocks, due to the different marine environment (different cooling, more constant high RPM's, etc). Chilton & Haynes manuals had to get their info somewhere. I think Toyota had different torque values based on whether the Supra came with a turbo, or not. Granted that is a bit different. Not trying to argue, just curious, always trying to learn something. And Jim you're right about the lube, if needed. That can make a huge difference. Another reason I stuck with a major manufacturer (ARP) and followed their installation instructions.

Why would indmar/pcm change torque values from the manufacture who designed and built the engine in the first place??

Ford engine repair manual states use engine oil on threads, torque in 3 steps, first to 85 ft-lbs then to 95 ft-lbs then to 105-112 ft-lbs

Ford has never used torque to yield bolts on the 351w

Here is a link for the ford marine engine repair manual

ftp://ftp2.indmar.us/Manuals/Service%20Manuals/Engine%20Mechanical%20Manuals/351%20Ford%20Manual.pdf

Kyle
10-20-2011, 01:55 PM
It can't get any more clear than this...

Kevin 89MC
10-20-2011, 02:48 PM
I think you guys missed my point, or more likely what I meant came off wrong. I have the same manual you do, and followed it when doing my headgasket. I was just wondering if Ford had different headbolt torque specs for their marine & industrial blocks, than for their street use blocks. It appears so, according to the first half dozen results from Google when I typed in "Ford 351 headbolt torque values". Most were 95-100, saw one at 85. Indmar states 105-112 for 1989, although Kyle I see in yours it states just 112. Out of curiosity what year is your book from?

I was just wondering if anyone knows for sure what Ford specified for their street blocks. It appears that Ford decided to put out a higher spec for torque on the marine/industrial blocks.

I'm not trying to disagree with anyone here, and sorry to the original poster for us getting pretty far off track. Just thought it was in interesting tangent.
Kevin

Kyle
10-20-2011, 07:14 PM
My book I believe is late 80's to early 90's. Don't hold me 100% to a year because it will make a liar out of me.

The next time I'm at the storage I'll look for a date.

rjracin240
10-21-2011, 11:50 AM
I'm not trying to disagree with anyone here, and sorry to the original poster for us getting pretty far off track. Just thought it was in interesting tangent.
Kevin[/QUOTE]

No worries what so ever, I am now printing off the Ford Industrial/Marine engine manual as I type this to use when I get into pulling my heads and repairing what I have.

Thanks Kyle, Peter, and Kevin for getting me all schooled up.

thatsmrmastercraft
10-21-2011, 12:00 PM
You can learn more here by accident, than on other forums by design.

Kevin 89MC
10-21-2011, 04:10 PM
You can learn more here by accident, than on other forums by design.

Another Garage Logic fan! I think the Mayor would like it here, all the boat & garage talk.

rjracin240
10-22-2011, 11:37 AM
It can't get any more clear than this...

Kyle, any chance that there is a link to that Indmar manual in PDF????

j.mccreight@hotmail.com
10-22-2011, 12:34 PM
once it loads you can save a copy, if you can't i can try to email you a copy...

ftp://ftp2.indmar.us/Manuals/Service%20Manuals/Engine%20Mechanical%20Manuals/351%20Ford%20Manual.pdf