New to Supra and looking for some help

[Chuck Yager]

Hey everyone, I want to start out by saying this is an awesome site. I was not at all familiar w/ supras when I started looking for a DD inboard. I saw a supra for sale and decided to do some research. All the knowledge on here and the passion many of you share for these boats pushed me to go ahead and buy one. I bought an 87 Sunsport Skiier with the Kevlar hull. It has the 351 Ford in it. It's in good enough shape to hit the water in and that was what I was looking for in my budget, especially since I was needing a good open bow boat to slalom and wakeboard behind. I found it about 4 hours away from my home and went 4 days after a record snowstorm in February to check the boat out. All the stringers appear to be okay and the motor started and ran well, so I paid the man his $4,800 and took it home.

Now on to the fun stuff..... I was itching to get the "new" boat put on the water for it's maiden voyage, and found a day that was decent enough to go. I installed the brass plugs back into the block and found a place for the smaller brass plug and went to the lake. I backed it in and the boat started with the bump of the key as it always has on the trailer. I let it idle for a bit and noticed the alternator wasn't putting out enough volts but decided to take it for a really quick trip just to get it on plane and see what it was like. I eased into the throttle and started to plane out nicely when I noticed a little bit of a smell like a hot motor and then heard a really faint high pitched tick. I looked down to see my water temp nearly to 250* and the boat started to lose power. I jumped out of the throttle and the motor came to a complete stop (without turning the key off). I did a dance and spoke in tongues for a few minutes after lifting the engine cover and smoke poured out. I decided to let the engine cool to see what was wrong. Long story short I had found the wrong place for the little brass plug that is supposed to be in the strainer/trans cooler. I did manage to get the engine to eventually turn over and start and I limped it back to the trailer without getting the motor smoking hot again. As would be expected I replaced the alternator, the starter, impeller, and the exhaust hoses which were fried from the whole debacle. I also put the brass plug where it belongs... I took it out on the water again and it starts effortlessly as is has before and the motor still sounds like it did prior to the incident. The exhaust manifolds are leaking water from somewhere (presumably a gasket that was fried). The thing that is puzzling me is the boat would only run up to 3,600 rpm at full throttle. It would also (presumably) load up and die if I was cruising and got out of the throttle very quickly at all and came to a stop and then be really stubborn to get started again as if its flooded. I'm not too sure of the reason it is doing these things. I am pretty mechanically inclined and understand most of the basics. However I am not familiar with ford engines or points type ignitions. I need some guidance. I intend to convert the ignition to the electronic ignition kit skidim has, but I want to figure out why I am not turning the rpm I should be according to the manual and according to what the PO told me before I do that. The other thing I am thinking about doing is putting the stock carb back on the boat. The PO had installed a Holley DP on it when he had an issue and thought it could be the carb. He later found it was bad points and gave me the stock carb as well. I am just not sure where to look or what to do with this problem or where to look first. I apologize for the novel and appreciate any help you guys can give me.

[duckseatfree]

I'm not very mechanically inclined but could it possibly be that one of the piston heads was damaged?

I also found the service manual for the 351....http://www.planetnautique.com/CorrectCraftManuals/PCMsvcmanual.pdf

its got a good diagnostics section...and also the 351 manual...
http://www.planetnautique.com/CorrectCraftManuals/PCMEngineOwnersManual.pdf

[jsandy]

hey man running one that hot for any period of time will A not burn a gasket and B most likely burnt up a few valves and piston rings. time to pull and rebuild. The faint high pitch ticking you were hearing was probobly detonation in the cylinders, this is caused by the gas exploding befor the sparkplug tells it to, this is obviously really bad. running one that hot is realy bad, you very easily could have warped or cracked a head.

[Chuck Yager]

Thanks, I found one manual over there earlier. Mabe this one will help shed some more light on the issue! I was concerned something could've gotten warped with all that heat. Hoping not to have to tear into the motor ofcourse. LOL!

[Salty87]

welcome chuck

you should give your new ride a proper tune-up (points, condensor, cap, plugs). you should always assume that the previous owner's head was way up his a$$ and be pro-active in fixing things. is the new carb marine? lots of boat owners assume that marine grade equipment is simply too expensive and then do dangerous things like using automotive parts. some auto parts are ok but anything with fuel or spark needs to be marine.

life will probably be easier if you get her running good with points and then start making upgrades.

don't forget to change your impeller.

[Chuck Yager]

JSANDY, thanks for the reply. Yeah, those are my fears. I am trying to keep an eye out for any blow-by or water in the oil to indicate some kind of issue like that. I do worry that something like that could've happened, but the other side to that is I am hoping that isn't the case. The motor sounded too good to think there is a problem, if that makes sense... No ticks, squeaks, misses, or stuttering. I didn't notice any blow-by or water in the oil either. I am going to put it on the hose sitting on the trailer and let it run and keep a real close eye on things to see if something jumps out at me. It makes me sick that a stupid mistake like that could've cost me the motor.

[Chuck Yager]

Salty, thanks. No the DP carb on the boat now isn't marine and the original one obviously is and that was my thinking. I don't really want non-marine parts on there. I was thinking I would dig into the tune-up option and swap the marine carb back on there and then go from there. I didn't know if the points or maybe a bad advance spring would cause it to sound like a champ and run seemingly fine except for the fact that 3,600 rpm is all I can get out of the motor under way when the PO said it would run at 4400 rpm @ WOT.

[Salty87]

that's why i suggest a routine round of maintenance to start. we can't assume the PO did it. and, if you don't knock those out first, you'll be throwing parts at it and that can get expensive. kiss.

[Chuck Yager]

I'm a big fan of that method! LOL!

[87SunSportMikeyD]

I have an 87 SunSport too, it's a great boat. I'm no mechanic, so I wont gum up your thread. Keep an eye out for a private marine mechanic on craigslist. They are a huge money savings vs if you have to go to the dealers.

[docdrs]

I'm curious, how fast are you going at 3600 rpm?

[Chuck Yager]

Thanks, I am too stubborn to have someone do it for me. I like the satisfaction of figuring it out myself, or not....That's when I will take that route. I hadn't thought to look on Craigslist though. Good idea!

[Chuck Yager]

I'm not sure. One of the speedo's was stuck. (need to clean the line I'm sure) The other one has cracked glass and the face has curled around the 25 mph mark so that needle would get stuck there. My best guess would be about 30-35, maybe. It didn't feel like 42-45mph for sure. It may be down in the power dept for some reason. IDK if the overheating caused something strange to happen with the distributor gapping or something like that or if something in the carb isn't happy and maybe a fuel passage got gummed up from being so hot.

I also noticed that the motor seemed to be creeping up a little in water temp when I was running it flat out. Doesn't a motor run hotter if it is lean? just a thought....

[jzelt]

I would say possibly fuel/air ratio.

On a hose, I wouldn't run it over 3000, but I would be "inclined" to but the throttle quickly to see if it would rev over that if you have no other mechanical issues.

It is possible it is over-propped, not allowing it to run it's potential.
(Had that happen on a Chaparral from previous owner, 21" and replaced with 17").

[jsandy]

i would suspenct a tuliped or burnt valve. that will cause the valve not to seal back into the head and cause it to run lean.

[Rusty]

I'm a big fan of that method! LOL!

Kustom motor out Dennison,TX (lake texoma) rebuilt my 87 supra saltare 454 pleasure craft engine (excellant good old boys) they will do it right! Another option would be city motor supply off of Harry Hines in Dallas where u can essentially swap out your motor

[Chuck Yager]

Jzelt- That's kindof where I am leaning... I checked w/ the previous owner and he told me it would run up to 4400rpm and I have no reason to not believe him. I put it on a hose yesterday afternoon and started it and it readily revved to close to 5k + rpm when i bliped the throttle. I did notice that the distributor cap was cracked. I didn't notice where there was any apparent tracking or any wierd burns like the spark was jumping around. i did seem to notice a bit of an occasional stutter/miss but nothing that was regular and would make me look to a specific cylinder as having a miss. I also pulled the #1 plug and it appears to be just like it should be. light tan/brown right where the spark is and a light amount of black on the rest.

jsandy- Wouldn't there be a dead cylinder if one of the valves were burnt, or some valvetrain noise? Other than an occasional stutter while idling, it seems to be running smoothly...

rusty-Thanks, I am thinking I am going to run a compression test on the cylinders to make sure they all have good compression since there isn't any water in the oil and no apparent vacuum leaks. I appreciate the suggestions. Its hard to find reputable places sometimes.

I have noticed some water leaking from the bottom of the exhaust manifolds. That couldn't be causing any kind of performance issues, could it? (I wouldn't think so, but I thought I'd throw that out there) I am having to rebuild the original carb before I put it on and get rid of the non-marine carb. Ordering stuff from skidim and going to replace the cap and see where I go from there. Sound like I'm on the right track? points looked okay/very recently replaced.

[Jetlink]

Not sure if this has been mentioned but, when I test drove my boat, it ran like a top. No hesitation, just grin inducing acceleration all the way from idle to around 4,400 RPM and that was good enough for me. Get the boat home and take it to some lakes near by that have no wake areas, boat starts hesitating and running rough. Long story short, come to find out the gap on the plugs is too big, and by a significant amount and on top of it, they had retarded the timing about 10 degrees off of TDC. That was the cause of my problem, after regapping the plugs according to the manufacturers specs and timing it, man it runs even better than the intial test drive.

[Chuck Yager]

I ordered a bunch of stuff from skidim:
a carb renew kit,
a new fuel line to replace the one "engineered" to fit the DP that was put on,
an electronic conversion kit to get rid of the points,
and a new distributor cap (since the old one is cracked).
I am going to pull all the plugs as you suggested and clean/re-gap them (just to be safe). I'm not exactly sure how I am going to check the timing though. For some reason, I can't find any timing marks at all on the balancer/pully..... I didn't discover this till I hooked the timing light up and started the motor to check the timing. I guess I will be having to set the timing by ear... any suggestions? It does start at the bump of a key now.

[Jetlink]

It has been years since I did this last but I had to help my friend set the timing on his truck without knowing TDC... If I recall, there is a way to rotate the engine through and find it on the number one cylinder when the piston is at TDC...do that and then mark the pulley for reference. Somebody else feel free to correct me if I am wrong on that procedure though.

[Chuck Yager]

Thanks! That's what I was thinking I would need to do. Find TDC on the compression stroke and start from there. I get my stuff in this weekend so I'll try to thrash and let everyone know what all happens when I get 'er put back together and in the water.

[Chuck Yager]

I just thought I would shoot an update to anyone who might happen to run across this again or was still interested.

I replaced the distributor cap,
installed the electronic pickup conversion kit,
Rebuilt the OEM MARINE carb and reinstalled it with a new fuel line from skidim,
oil and filter change (ofcourse).

I bought a compression tester and got back good numbers off of a cool engine. (I know it is best to do it w a warm engine, but I felt that doing this would still give me the info I am looking for.) I had readings from 145-132psi so it appears everyting checks out there! Whew! What a relief! I haven't been able to take it to the lake to see how it runs on the water, but it sounded good on the trailer. I do have a bit of fine tuning to do with the idle, but the weather and my spare time have not been cooperating with me well lately. I haven't touched the actual timing yet since I didn't have any marks on the balancer and the PO seemed to have it dialed in. It would start w the bump of the key. Also the leaking water from the manifolds was from the PO's JB Weld job on the manifolds... I plan to do the same thing for the moment to get me by until this winter when I can save up some $$ to replace the manifolds as they should be.

Now I have moved on to other things for the moment. I cleaned the connections for the gas guage since it wasn't working, and I unclogged the vent fitting on the tank. I should now be able to fill the tank at a rate faster than I could relieve myself. LOL! I'm also working on rebuilding the seat back for the playpen area. I also have found a couple of cracks in that area where the cushions would sit. Has anyone had any luck/experience w/ that evercoat tigerhair? I never have done body work/fiberglass repair, but that sounded like a good thing to use to correct the cracked areas. Any thoughts/opinions?