Thread:

3rd motor in 3 years

I have a 1978 crusader mini day.
I have a basicly stock chevy 2 bolt main 454. has airgap intake hardin headers and a demon 800 carb.

anyway i have had the boat on the water for 3 years and i have blown up three motors.

i have used the same engine builder every time. so i think that is going to stop.

but before i spend more money on a new motor i am wondering if my boat could be causing this.

the motor is 3 pointed in the boat. has a panther jet so the bell housing clamps right to the pump and i put a bbc mount plate on the front.

I want to know if there isany way my boat is damaging the motors.

the first time i spun the bearings out of the motor cant remember what happend the second time and this time i found the cam broken in half and pieces of piston in my oil pan.

two weeks ago i took the boat to mead and it ran great. i did not notice any noise when putting it onthe trailer. i brought it home and the next time i tried to start it in the back yard. i heard a clucnk and the motor stoped. i thought the starter was stuck. but after digging into the motor i found it was blown up pretty good.

any insight would be helpfull. i can supply pics if you need them. thanks

this is the motor when i pulled it out yesterday


here is the back of the boat


the front of the boat


with the engine cover off


well that is all i could pull up right now

We need a pic of the girl in the boat.

Were any engines dyno'd?


Uncle Dave

Originally Posted by Uncle Dave

Were any engines dyno'd?


Uncle Dave

no just did a cam break in when it was installed in the boat.

How much oil did you drain out of it?

Originally Posted by EVILFORCE

How much oil did you drain out of it?

i just put ten quarts in the week before this happend? i am not sure it was an oiling issue but could be.

Might need to lighten the foot pressure.

If I were a betting man I would be taking a real close look at your exhaust system.The P 1000's that you are running have a real bad problem leaking internally.Cold water on a hot exhaust valve means that failure is in your future. Take a flash light after you pull the exhaust off and check the exhaust valves my guess is that you have broken the head of an exhaust valve off.

i will look into that as well. i have hooked the headers up to my hose and found no leaks. they are a little old and the exit section i had to lengthin to fit in my boat. but they work way better than the logs and snails that were in the boat.

nope never gut a build sheet. i got a reciept for damaged pistons borke crank new cam new gaskets seals and bearings. all the normal stuff. but never a build sheet that states bore size clearance or settings.

there are splines visible on the pump shaft going into the H joint. I need to double check that alignment before i put a new motor in it.

what is the best way to do that just put a dial gage on it and do some triangle measureing?

i cant narrow it down to a cylinder. the last time it was a bearing this time complete distruction. i wil lknow more when i go to the engine shop today and see if they have taken it apart yet.

i would say in a day we probably only do about 15 mins of actual boat time. and that is pushing it. I do like to go fast. but i never pull skiers tubes or anything like that. if i do run flat out it will hit about 5700rpm and i may run it wide open for maybe 30 sec at most. if someone is racing me back to camp. by then we have usually established who is faster so no more reason to race.

This problem is just getting very expensive and i want to find what it is and correct it before the next motor goes in.

thanks again for all your help i will check all areas of concern asap.

Shoemakers been around the block a time or two, (no disrespect Greg to speak on behalf of you in the third person) I think Id take a look and see if you have the valve damage he describes.

We're all going to and zero-ing in on your exhaust though as the most likely suspect and after that ...junk/cheap parts. If you are being level with us.

Heres the thing, the lack of a build sheet or a dyno run is the earmark of a less than desirable situation, and brings into suspicion use of the cheapest stuff available. It may be true it may not be true, but you dont really know do you? all you have is a third blown engine a lighter wallet, and a question mark.

Always insist on a build sheet, this way if you have a partial failure you can at least know what parts are in there to go get 1 or 2 of. Without this you are just guessing. and a guy you take it to to fix it up later doesn't know what hes dealing with, or what to match with what.

If you dont mind sharing what did you pay for these fresh ups/rebuilds from your mystery man that uses mystery parts?


Uncle Dave