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badgerjfr
09-04-2012, 02:55 PM
hey all,

i've been working on a 1984 stars and stripes, after 3 months finally got the thing to run and go. now my problem has changed

the boat seems to dog out a little on take off and max rpm i can achieve is around 3300 at around 34 mph. im not 100% sure, but i think i should be able to get closer to 4400rpms and 45mph. aside from that the engine runs very well while idleing and in gear i just think theres something im overlooking thats holing back the capabilities of the engine.

the boat has a rebuilt 351w, new plugs and wires, new alternator, put in an electric fuel pump, rebuilt 4160 holley carb, rotor, distributor, fuel lines, fuel filter, and i cant think of much else to replace to get the desired speed and rpms. the only two things i can think of are replaceing the coil, and possibly replacing the plugs with a high preformance ones.

im getting really close to getting the mechanical end of the boat in great order and would love to get a little advice from anyone. i searched the forum for about 10min and couldn't find a thread on this issue, but im sure someone has had a similar problem. thanks again
-jeff

cbryan70
09-04-2012, 02:57 PM
What prop do you have on it? Is it 1 to 1 or a slot tranny?

badgerjfr
09-04-2012, 02:59 PM
4 blade 13" prop and a 1 to 1 ratio trans.

EJ OJPROP
09-04-2012, 03:01 PM
The 13 X 13 should let the engine turn up higher than 3300.

etduc
09-04-2012, 03:41 PM
You are 1100 rpm, below avg peak, for that engine. Spark plugs, ain't going to get you there.

You said your carb was rebuilded, don't assume it was done right.
You said new electric fuel pump? Are you sure you are, feeding the engine, enough gas. Always go to basics first. Fuel, air, spark. I would suspect secondaries not, engaging. and/or distributor not advancing correctly. or Combination of both. What does the color/condition of your existing spark plugs?
Even with a couple of runs, they will show signs of fueling issues, if any.

Motor heads should be long, with better advice.

badgerjfr
09-04-2012, 04:58 PM
elctric pump was putting out 8 psi, a motorhead buddy told me to put a regulator on it and keep it at about 5.5 psi. the engine ran the same at 8 or 5. even started playing with the regulator last weekend and noticed at about 3.5 psi the engine seemed to be "starving" but never died on me so i put it back to 5 psi.

as for the carb, i mailed it to a place in florida and they rebuilt it. the thing looked bran new when i put it back on the boat. they supposedly pressure test everything, and set it for your engine before sending it back, so all you have to do it put it on the engine. they offered a lifetime warrant on the carb for an extra $29 so i bought that. maybe sending it back to have them work on it again would be a good idea for the winter. i don't know too much about the carb but don't notice any vacuum sounds. like i said the engine sounds and runs great im just not getting the top rpms and speed i should be.

as for the plugs i have not pulled them yet to check color. i should be able to do that soon.

thatsmrmastercraft
09-04-2012, 05:22 PM
It sounds like you have the basics of plugs, cap & rotor, fuel filter and line checked off the list, at least for now. The two most likely causes of insufficient RPM are stuck distributor advance weights and a bad secondary diaphragm in the carburetor. Both are easy to check. Your timing should be at 8-10 degrees BTDC at idle speed of 800 RPM. Goose the throttle up to 2000 RPM and watch the timing climb....or not. With the boat in the water, not in the driveway, take her gradually to full throttle and listen. If your secondaries are kicking in, you will hear it.....or not.

thatsmrmastercraft
09-04-2012, 05:24 PM
Hey badgerjfr, where in the Midwest are you. I'm in St. Paul......I'm assuming you are in the land of cheese?

Dishz
09-04-2012, 08:51 PM
I'm badgerjfr's brother. We are located in the La Crosse area. I was with him in the boat this weekend with our friend working on it. As for the primaries and secondaries, he was manually holding them all open with no difference in rpm or speed. He has a feeling it has been getting too much fuel. Also, could it be a lack of spark? Compression problems? If anyone is running the same motor and/or carb, what size jets do you have on both the primary and secondary? Finally, any tricks on the ability to test the fuel to air mixture? Can't stick the sensor in the tailpipe, obviously. Any help is appreciated! Thanks!

Dishz
09-04-2012, 08:55 PM
Another prop question. Anybody have any idea what the stock prop that came on the boat (84 SS 1:1)? I've noticed a lot with 3 blade, and a lot with 4 blade. With this tranny, what prop do you folks suggest? I like to have hole shot and top end, but if I had to lean a bit one way or the other, I guess more top end would be better (for footin'!!).

thatsmrmastercraft
09-04-2012, 10:26 PM
I think the 13x13 3 blade was still the stock prop. If you want some real prop advice, give Eric at OJ Props a call. 865-458-5205 http://www.ojprops.com/

You should have #66 jets. Have you pulled a couple plugs to read the color?

As I mentioned before, I would check to make sure the distributor is providing sufficient advance next. There have been several guys on here this year with this exact symptom which turned out to be rusty, stuck or broken advance.

Dishz
09-04-2012, 10:37 PM
Haven't had a chance to pull the plugs yet. Probably tomorrow night. I'll post once I get to it. Thanks again.

thatsmrmastercraft
09-04-2012, 10:39 PM
That's what we're here for. Keep us all happy and post some pics.

Dishz
09-04-2012, 10:49 PM
83900

83901

thatsmrmastercraft
09-04-2012, 10:56 PM
Looks great!

j.mccreight@hotmail.com
09-04-2012, 10:58 PM
Another prop question. Anybody have any idea what the stock prop that came on the boat (84 SS 1:1)? I've noticed a lot with 3 blade, and a lot with 4 blade. With this tranny, what prop do you folks suggest? I like to have hole shot and top end, but if I had to lean a bit one way or the other, I guess more top end would be better (for footin'!!).

13x13 3 blade was oem, 13x13 4 blade will be good for hole shot without sacrificing top end, talk with eric from oj prop for your specific need...

only way to tune a carburetor is with a vacuum gauge...

etduc
09-04-2012, 11:36 PM
Nice looking boat.

I would confirm distributor is advancing correctly. Stuck advancer, springs, corrosion,etc. My Tristar was so badly corroded, it wouldn't advance smoothly. They can be rebuilt, I replaced mine, but it was rebuildable. Distributors are cheap. If yours still has points, you might want to consider electronic replacement.

Check your plugs. Typically, a lean condition engine will want to rev, but will buck pop, run ruff. Rich it will bog down, then clear, except in extreme conditions. In both cases, engine won't reach max rpm.

You will have to check your advance, under load, on the lake. Get the advance timing number, off the internet, for a Ford 351w. Doesn't matter street or lake, advance timing will be the same. You need to get it, in the ball park.

Don't throw parts at it. confirm the plugs 1st. Do a compression test. More motorheads will appear.

Like I said, really cool boat.

j.mccreight@hotmail.com
09-05-2012, 12:51 AM
If the distributor springs, weights and plates are corroded or broke upgrading to electronic ignition will not fix the mechanical advance the distributor is going to have. Checking the total advance of the distributor does not need to be under engine load while driving boat, it is centrifugal advanced not vacuum advanced. My 351w once had a bad(torn) secondary diaphram that limited my engine to around 3000 rpm under load, I would check the carburator again.

MikeyOrange88
09-05-2012, 01:53 PM
If the distributor springs, weights and plates are corroded or broke upgrading to electronic ignition will not fix the mechanical advance the distributor is going to have. Checking the total advance of the distributor does not need to be under engine load while driving boat, it is centrifugal advanced not vacuum advanced. Should have 34-36 degrees of total timing around 3000 rpm's.
If your distributor is all fubared weights and springs are not sold for this prestolite anymore and you can drive yourself crazy trying to use GM hei tuning kits and trying to file down cams and change springs, just call prestolite performance 1-216-688-8300 techline and they can sell you a reman for $125 although turnaround time is 10-14 days and it is also upgraded with EI, and it will have the proper 24 degrees of mechanical advance already built in.
I recently played this distributor song and dance as I was getting 29 degrees of total advance at 3000, now I get 36 degrees at 3100 rpm's. But even with my distributor woes I was still turning 4600 rpm @ 43-44 mph, My 351w once had a bad(torn) secondary diaphram that limited my engine to around 3000 rpm under load, I would check the carburator again.

Don't mean to hijack your thread here, but I've been working on my '88 Tristar 351W and also seem to be having some advance or secondary issues as well as I can only get about 4000-4100 rpm and around 40 mph. Prop is the stock 3 blade 13x13. Compression was 130-132 on all cylinders (except no. 8 which was 125 and had a leak in the head) before I changed out the heads. I just replaced them with GT-40's, carburator was rebuilt prior to changing the heads, new plugs, new fuel filter. Distributor does not have points, but not sure what brand it is. I didn't have any issues with reinstalling the distributor as it went right in on my marks and timing checked out at 10 BTDC. It is advancing, at least somewhat, as it is getting up to around 20 degrees total around 2000 rpm judging from the distance from 0 to 10, while sitting on the rack. I haven't been able to run it while looking into the carb to check the secondaries, but I'm not feeling or hearing them open. The linkage seems to working correctly on the carb. Any ideas on things to check. I'm going to run it with a helper this weekend so I can use timing light and check secondaries up to a higher rpm. I've appreciated all of the TT posts as I usually lurk in the background and just search and read when I have an issue. I like to read your replies since you seem to have a similar boat.

MikeyOrange88
09-05-2012, 01:58 PM
Also, I can say from about the 9:00 throttle position on down to 7:00 position adds no speed or rpm's (or maybe any fuel?). How is fuel pump tested for pressure? The engine runs pretty dang good otherwise. Just trying to get everything out of those GT-40's.

ski_king
09-05-2012, 02:03 PM
Just a long shot, but.....

It may be an illusion from the rough water, but it looks like the boat is riding deep in the water. Are you sure the floor isnt waterlogged and you are dragging aroung extra weight?

markismm
09-05-2012, 02:10 PM
You could always have someone else ride with you with the doghouse off and check to see if your secondaries are opening all the way. You can also manually open them while driving. If the secondaries are coming all the way in when all full throttle, I would get a timing light and determine the total amount of timing advance you are getting out of the distributor. It should be set stock somewhere between 8-12 degrees before top dead center (everyone will tell you different and it really depends on all of the motor components). At wide open throttle, you should be getting a total of 30-36 degrees of total timing advance (I know this is a wide range, but if you are somewhere in there and you motor is not getting above 32-3300 rpm with the secondaries fully open, then you likely have a fuel delivery problem). Again, the total timing advance is going to be dependent on what your initial timing is and the distributor set-up you have. I believe that one of these items should be your culprit. Why did you go to an electric fuel pump by the way. I have the exact same boat (84 - red and tan). Love it. The best purchase I ever made. See my pics below.

http://i170.photobucket.com/albums/u280/mandymaholick/2011-10-22_16-22-17_566.jpg

http://i170.photobucket.com/albums/u280/mandymaholick/DSC_0735.jpg

thatsmrmastercraft
09-05-2012, 02:16 PM
Don't mean to hijack your thread here, but I've been working on my '88 Tristar 351W and also seem to be having some advance or secondary issues as well as I can only get about 4000-4100 rpm and around 40 mph. Prop is the stock 3 blade 13x13. Compression was 130-132 on all cylinders (except no. 8 which was 125 and had a leak in the head) before I changed out the heads. I just replaced them with GT-40's, carburator was rebuilt prior to changing the heads, new plugs, new fuel filter. Distributor does not have points, but not sure what brand it is. I didn't have any issues with reinstalling the distributor as it went right in on my marks and timing checked out at 10 BTDC. It is advancing, at least somewhat, as it is getting up to around 20 degrees total around 2000 rpm judging from the distance from 0 to 10, while sitting on the rack. I haven't been able to run it while looking into the carb to check the secondaries, but I'm not feeling or hearing them open. The linkage seems to working correctly on the carb. Any ideas on things to check. I'm going to run it with a helper this weekend so I can use timing light and check secondaries up to a higher rpm. I've appreciated all of the TT posts as I usually lurk in the background and just search and read when I have an issue. I like to read your replies since you seem to have a similar boat.

Correct advance and secondary operation are the two most likely culprits.

jay
09-05-2012, 02:39 PM
Correct advance and secondary operation are the two most likely culprits.

x2 agree

JMann
09-05-2012, 03:33 PM
Do you have ballast in there in the picture? It's seems to be riding to low in the water.

j.mccreight@hotmail.com
09-05-2012, 03:42 PM
Don't mean to hijack your thread here, but I've been working on my '88 Tristar 351W and also seem to be having some advance or secondary issues as well as I can only get about 4000-4100 rpm and around 40 mph. Prop is the stock 3 blade 13x13. Compression was 130-132 on all cylinders (except no. 8 which was 125 and had a leak in the head) before I changed out the heads. I just replaced them with GT-40's, carburator was rebuilt prior to changing the heads, new plugs, new fuel filter. Distributor does not have points, but not sure what brand it is. I didn't have any issues with reinstalling the distributor as it went right in on my marks and timing checked out at 10 BTDC. It is advancing, at least somewhat, as it is getting up to around 20 degrees total around 2000 rpm judging from the distance from 0 to 10, while sitting on the rack. I haven't been able to run it while looking into the carb to check the secondaries, but I'm not feeling or hearing them open. The linkage seems to working correctly on the carb. Any ideas on things to check. I'm going to run it with a helper this weekend so I can use timing light and check secondaries up to a higher rpm. I've appreciated all of the TT posts as I usually lurk in the background and just search and read when I have an issue. I like to read your replies since you seem to have a similar boat.


Sounds like your on the right track, is the performance the same before and after the head swap? you will need an advanced timing light to check the advance or you will need to add a timing tape to the balancer to properly check the advance, checking timing does not need to be under a load but checking carburetor does, if you don't have a helper put a fairly loose paper clip on secondary linkage then go out and run it if the paper clip moves then the secondaries are moving and should kick in the 3000 rpm range. Checking fuel pressure just entales putting a gauge inbetween the pump and carburetor and will need to be in the 6-7 psi range. When you are checking this stuff for giggles remove the fuel filler cap if performance instantly increases then the fuel tank is going into a vacuum and starving the engine of fuel, the vent hose and anti siphon valve needs to be checked.

MikeyOrange88
09-05-2012, 04:04 PM
Thanks J. Pretty sure the issue was there prior to head replacement as I don't normally run it up there too much. I'm thinking it is the secondaries. But I will try the fuel vent test, hadn't thought of that. Doesn't really seem like a fuel pump supply issue because it runs great otherwise. The GT-40's feel more responsive than the old heads on the low end. I just need to get someone else in the boat with me. BTW, did you replace your distributor with a rebuilt Prestolite model or change to a new EI of some type. I've read so much positive and negative on the Pertonix that I'd be afraid to change it, unless I can verify it is just not functioning correctly.

badgerjfr
09-05-2012, 04:27 PM
as for the fuel pump, i picked it up at a local motor parts store, along with the pump cover plate, hoses, filter, and regulator. the place is pretty awesome. they have a large variaty of products on hand along with a fair amount of marine rated products.

no ballast in the boat. i think crafts from that era tend to sit a bit lower than usual, but is was quite choppy on the river that day. when the boat is just floating the teak sits just above the water if not on the water depending where people are in the boat. she planes out really nice when under power.

does anyone think the coil could be causing some issues. its one of the few things i havent replaced yet, and probably will anyway just because its not too expensive.

the distributor isn't the original but it came with the craft when i bought it. what/where am i looking for the rusty, seized advance pieces/weights. or would it be easier just to replace the whole thing.

thatsmrmastercraft
09-05-2012, 04:32 PM
Usually a coil will just fail, but you can have an internal short that would limit it capacity. Not a likely fix, but not unheard of either.

j.mccreight@hotmail.com
09-05-2012, 04:40 PM
Thanks J. Pretty sure the issue was there prior to head replacement as I don't normally run it up there too much. I'm thinking it is the secondaries. But I will try the fuel vent test, hadn't thought of that. Doesn't really seem like a fuel pump supply issue because it runs great otherwise. The GT-40's feel more responsive than the old heads on the low end. I just need to get someone else in the boat with me. BTW, did you replace your distributor with a rebuilt Prestolite model or change to a new EI of some type. I've read so much positive and negative on the Pertonix that I'd be afraid to change it, unless I can verify it is just not functioning correctly.

Initially I swapped to the mallory e-spark ei conversion about 3 years ago, and recently i replaced with mallory unilite billet distributor assy

badgerjfr
09-05-2012, 10:36 PM
markismm... beautiful boat. i hope to get this one looking that nice someday, but it will probably have different interior design.

markismm
09-06-2012, 02:00 PM
I dont think you should be afraid of swapping to a marine billet Pertronix Distrib. Just put on in my boat at the beginning of this season to replace my old converted Prestolite and it is working flawlessly. Again, I have the exact same boat with a 351w, GT-40 heads and a Performer Intake. The boat has never run as good as it does now. Again though, no need to replace unless its not doing its job. I would first check your socondaries before doing anything else. This is the easiest thing to eliminate as the culprit.

thatsmrmastercraft
09-06-2012, 02:06 PM
:popcorn::popcorn::popcorn:

MikeyOrange88
09-09-2012, 11:30 PM
I dont think you should be afraid of swapping to a marine billet Pertronix Distrib. Just put on in my boat at the beginning of this season to replace my old converted Prestolite and it is working flawlessly. Again, I have the exact same boat with a 351w, GT-40 heads and a Performer Intake. The boat has never run as good as it does now. Again though, no need to replace unless its not doing its job. I would first check your socondaries before doing anything else. This is the easiest thing to eliminate as the culprit.

Finally got the boat out with someone to drive. Secondaries did not open, but I could manually turn the throttle and get them opening. Removed the choke and secondary assemblies. Checked diaphram orientation with the vent hole and tested diaphram and it did hold a vacuum. Reassembled and tightened everything down and got them to work. I guess there was a small leak there somewhere. Centrifugal advance on the distributor moved up to about 25 degrees BTDC, idling at 10 BTDC. Up to 4400 rpm and right at 42-43 mph by my speedos. Going to dig into the distributor and clean/lube the springs and plate to verify all is good there. Getting pretty good performance

Also, never realized there was filter in the fuel pump as the pump is apparently the original model (things you can learn on Teamtalk). I have always cleaned and/or replaced the water separator filter element (Racor 110). Didn't look bad at all but I've got two ordered anyway. Thanks to all Team Talk for the help.

JMann
09-10-2012, 12:47 AM
What are you going to use to clean and lube you distributor? I would like to put that on my list for this off season but I am not sure how to do it.
Please post and let us know how you did it and if it helped
Thanks

MikeyOrange88
09-10-2012, 04:23 PM
What are you going to use to clean and lube you distributor? I would like to put that on my list for this off season but I am not sure how to do it.
Please post and let us know how you did it and if it helped
Thanks

Well, hadn't got that far yet. By the looks of it, there isn't much there in the way of crud. I've read on other posts where spring corrosion could be an issue, that is what i'm really looking for. Going to probably use some silicone spray or perhaps WD-40 type lubricants to insure the weights are moving freely.

thatsmrmastercraft
09-10-2012, 05:51 PM
Finally got the boat out with someone to drive. Secondaries did not open, but I could manually turn the throttle and get them opening. Removed the choke and secondary assemblies. Checked diaphram orientation with the vent hole and tested diaphram and it did hold a vacuum. Reassembled and tightened everything down and got them to work. I guess there was a small leak there somewhere. Centrifugal advance on the distributor moved up to about 25 degrees BTDC, idling at 10 BTDC. Up to 4400 rpm and right at 42-43 mph by my speedos. Going to dig into the distributor and clean/lube the springs and plate to verify all is good there. Getting pretty good performance

Also, never realized there was filter in the fuel pump as the pump is apparently the original model (things you can learn on Teamtalk). I have always cleaned and/or replaced the water separator filter element (Racor 110). Didn't look bad at all but I've got two ordered anyway. Thanks to all Team Talk for the help.

Is the throttle opening all the way when the throttle lever is at full throttle? You can check this with the engine off and look down the carb to see if the throttle and carb are adjusted properly. If the throttle isn't opened far enough, the vacuum can't get low enough to allow the secondaries to open.

j.mccreight@hotmail.com
09-10-2012, 05:58 PM
Well, hadn't got that far yet. By the looks of it, there isn't much there in the way of crud. I've read on other posts where spring corrosion could be an issue, that is what i'm really looking for. Going to probably use some silicone spray or perhaps WD-40 type lubricants to insure the weights are moving freely.

Use light motor oil... Should do this at 100 hr or annually...

88 PS190
09-10-2012, 10:48 PM
Also, never realized there was filter in the fuel pump as the pump is apparently the original model (things you can learn on Teamtalk). I have always cleaned and/or replaced the water separator filter element (Racor 110). Didn't look bad at all but I've got two ordered anyway. Thanks to all Team Talk for the help.

Something you may also want to check (and probably is not related to your issue). We had a very similar situation this summer, but with cutting out as well.

On the tank on our boat there is a Fitting for the fuel line to enter the fuel tank, this fitting is a 90 degree elbow, threaded into a plate on the tank, with a rubber tube pick up line that goes down into the tank.

This pick up line has a weighted end to keep it from floating, and a spring coiled up inside to keep it stiff. In our boat this spring acted like a filter, over the years picking up enough fiber to create a "prefilter" before the racor 110, before the bowl on the mechanical pump, and before the screen on the carb. So when it started cutting out it took awhile to suspect the actual tank.

MikeyOrange88
09-11-2012, 09:26 AM
Hmmm.... Something else to check as I've never opened up the fuel tank pickup. I've got a couple other fuel related items to do this weekend as well. Got the fuel filters and I didn't check the gas cap vent system yet either. Need to get some pictures to post also. Love looking at the pictures others have posted. Thanks.

JMann
10-10-2012, 12:59 AM
Use light motor oil... Should do this at 100 hr or annually...

Would you clean out the distributor with a WD-40 type spray then put a coupe drops of 10-40 oil on the springs? How should I clean my point or should I, do you put oil on the point or just the springs? it's running fine now I don't want to open a can of worms I don't need to but I would like to do this during the off season to get ready for next summer

j.mccreight@hotmail.com
10-10-2012, 01:06 AM
Would you clean out the distributor with a WD-40 type spray then put a coupe drops of 10-40 oil on the springs? How should I clean my point or should I, do you put oil on the point or just the springs? it's running fine now I don't want to open a can of worms I don't need to but I would like to do this during the off season to get ready for next summer

I would not just randomly spray wd-40 inside the distributor, the points get cleaned by filing a little and don't spray them, I see no problem carefully spraying springs and the cam plate, mostly what needs lube is the wire mesh pad that sits under the rotor that lubes the distributor bushing.