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watersports guy
04-05-2011, 12:29 PM
I bought a pair of heads, had them rebuilt and im getting ready to installe them.
Ford 351 91, pro star 190 with 1300 hours. I should have all the gaskets And everything i need to do the job. any suggestions? Just looking for some advice as this will be the first time im doing a major repair to the most imortant thing in my life. uh i mean besides my girlfriend.....

Table Rocker
04-05-2011, 01:15 PM
One thing I have done to make installing heads easier (while working on an auto engine still in it's bay) is to install long headless bolts in the block to slide the head down during installation. I bought concrete anchor bolts that were the same size and thread as my head bolts and cut off the bend. I put them in the top corners of the block, slipped on the gasket and slid the head right down the bolts. It made it easy to install without damaging the gasket or anything else. Install a few of the other bolts loosely, remove the alignment bolts and replace with your head bolts. Torque to specs using the recommended torque pattern. You should be able to find a diagram for the torque process.

Working on a direct drive, it should be pretty easy to reach and your alignment dowels might be enough. If you have any trouble handling the heads comfortably, get some bolts.

http://www.everything-about-concrete.com/images/j-bolt.jpg

markismm
04-05-2011, 01:25 PM
Along the same lines as the post above - have an extra set of hand available (a friend or family member - not your wife). You can usually grab the head the easiest by partially installing a couple of the rockers and grabbing those.

watersports guy
04-05-2011, 08:22 PM
thank you gentleman keep up the good work....

JLeuck64
04-05-2011, 09:08 PM
How does the finish on the cylinders look? Can you still see the cross hatch from the honing process or do they look to be mirror smooth?

matt
04-05-2011, 11:41 PM
ARP headbolts, a good torque wrench, and fel-pro head gaskets

watersports guy
04-06-2011, 10:12 PM
Got the gaskets from skidim. I haven't pulled the old heads off yet J why do you ask?

Laurel_Lake_Skier
04-06-2011, 10:40 PM
If you have a digital camera, take a bunch of pictures before you start pulling things apart. You'll likely want to refer to them to check routing of wires, location of brackets and things like that. As you disassemble, zip-lock bags with labels will help you be sure to get the right bolts back to the right spots.

As Matt mentioned, the ARP bolts should replace the original head bolts which shouldn't be reused. You'll also want some assembly lube.

A bit of fair warning, the old heads may be a bit tough to get off. The gaskets may have sealed them down to the block pretty well and need a bit of "persuasion" before they will break loose.

JLeuck64
04-07-2011, 12:16 AM
Got the gaskets from skidim. I haven't pulled the old heads off yet J why do you ask?

I don't know the whole story why you needed to replace the heads... but if I were in your shoes and with the age/hours on the engine I would budget for going through the bottom end at the same time. If the cylinders walls still had good cross hatch when I got things apart... I'd throw on the new heads. If the cylinder walls looked worn on the major thrust surface side (polished to a mirror finish) I would freshen up the bottom end.

It's just in my experience I really hate doing things half-way, and it's not that much more work to make it a GOOD runner once the heads are off. ( ;

watersports guy
04-07-2011, 08:28 AM
I foud a crack in the water jacket of the old head it sprays water at hi rpm's, i jb welded it and it has stopped. I would like to do the bottem end as well just not sure what its going to cost. My speed shop guy said i can probaly get a rebuild kit for about five hundred bucks, does that sound average? I hate doing things half way as well im just scared that crack will get worse and ill end up needing an engine? If i do decide to do the lower i suppose i should do the trans too... Its a buitifull boat and i plan on keeping it for a while.

Thanks for your help guys

Dino Don
04-07-2011, 08:43 AM
When mine was about two years old I had a noise that sounded like a knock. When I found it--the cylinder wall had a pin hole and let a small amount of water in. Replaced the block and balanced the rotating assy. Best thing I ever did was the balance work. Put flat top pistons and minor head work. Fixing to replace the heads with GT40P's with updated cam.

You might seriously consider doing the bottom end with those hours on it-rings and bearings with balance work. Sometimes sealing up the top end will make any weak areas in the rings and fit which will cause oil usage to become an issue especially on higher miles/hours engines. ??????

thatsmrmastercraft
04-07-2011, 10:02 AM
When mine was about two years old I had a noise that sounded like a knock. When I found it--the cylinder wall had a pin hole and let a small amount of water in. Replaced the block and balanced the rotating assy. Best thing I ever did was the balance work. Put flat top pistons and minor head work. Fixing to replace the heads with GT40P's with updated cam.

You might seriously consider doing the bottom end with those hours on it-rings and bearings with balance work. Sometimes sealing up the top end will make any weak areas in the rings and fit which will cause oil usage to become an issue especially on higher miles/hours engines. ??????

Very well said. At 500 hours on the engine I would put fresh heads on and not give it a second thought. 1300 hours is a whole different story. It also depends on how you use the boat. If the works is mostly wakeboarding engine effort is a lot different than if you do a lot of barefooting or just WOT running.

If you do the whole engine, you could realistically put the trans work off for a while. Pulling just the trans isn't too involved.

watersports guy
04-07-2011, 12:33 PM
That makes good sense Mr.mc my machine shop said about four grand to do the whole thing :( this might have to wait till next year, i ski the course and barefoot alot. not to much wakeboarding behind this boat. What do you think about keeping my new heads in the box and nursing that jb weld through another year?

TRBenj
04-07-2011, 01:22 PM
I disagree entirely. If well maintained, I would have absolutely no qualms about bolting a new set of heads on a motor with 1300 hrs. I did exactly that at 1200 hrs on my boat.

If those heads are cracked externally, how long before they leak internally? If they start letting water into the cylinders, more damage will occur. Put the new heads on with new gaskets and be done with it. Dont tear into the bottom end until it needs it- do a compression test if youre unsure of its condition. If you check out alright now, proceed with the head replacement.

$4k to rebuild the short block is highway robbery, by the way. That should be a $1500-2000 job, MAX.

matt
04-07-2011, 10:37 PM
before I got that deep, I would check the compression (cranking pressure). If all the cylinders looked good, I likely wouldn't go into the bottom. $4k sounds very high. I just rebuilt my LT1 this winter and it was less than 2k. the block was bored,the crank and rods checked at the machine shop, new bearings, new pistons and moly rings, NEW aluminum heads, timing chain, gaskets, water pump, ect. Ask questions

watersports guy
04-08-2011, 07:55 AM
Thanks Matt Ill do the compression test and see what i get, the mannual i have is from skidim off the idmar downloads page. does any one know if that is a good one? Its the ford 351.

matt
04-08-2011, 10:13 PM
I have a LT1 and I bought the chevy indmar manual and the borrowed the Corvette manual fron a friend. Both were helpful but getting into the engine, the corvette one was more helpful with the specs. Just my two cents, but if I was to go into the engine, I would but a engine manual from somewhere like Jegs or Summit.