1996 Prostar engine question

I have a 96 Mastercraft with a 350 Chev motor. Did the original motor have a four bolt main? A local engine rebuilder claims a two bolt is just fine. Anybody know for sure?
Thanks Brad

[JimN]

Standard Chevy truck motor.

What is causing your concern?

The original motor was shot. We ordered a new motor from an online re-manufacturer who said the motor he was selling us was the exact replacement. We bought the motor, had it installed and after 5 hours of use had water in the cylinders, which is typically a head gasket. He said we must pay to have the motor removed and send it to him for him to look at. Not a reasonable answer. The original motor had a four bolt main and the one he sold us has a two bolt main. My answer to his bad answer. All I want is a motor that runs and I don't think it's fair for him to require us spending another $1400.00 to R&R the motor for a bad gasket.

[blackcreek]

What was the problem with the original motor that was replaced? Water can get in the motor through the head, head gaskets,block, intake manifold or gasket, or exhaust manifolds if anything is cracked or not seated correctly. The lower block crankshaft main caps being two or four bolt probably has nothing to do with your water leak. Four bolt simply means the lower main bearing caps are held on with two extra bolts which helps keep the crankshaft main bearing tolerances in spec at very high horsepower or rpm levels. If you had a rod knock or bearing problem right away I would blame the lower block assembly but I don't see the block being a problem in this case unless they used a cracked block for the build. Some rebuilders sell a premium package which includes labor costs in the case of motor problems but most just cover the warranty on the motor itself, install/removal costs in most cases is up to the buyer. You need to read the fine print when buying a rebuild.

[JimN]

Originally Posted by Brad B

The original motor was shot. We ordered a new motor from an online re-manufacturer who said the motor he was selling us was the exact replacement. We bought the motor, had it installed and after 5 hours of use had water in the cylinders, which is typically a head gasket. He said we must pay to have the motor removed and send it to him for him to look at. Not a reasonable answer. The original motor had a four bolt main and the one he sold us has a two bolt main. My answer to his bad answer. All I want is a motor that runs and I don't think it's fair for him to require us spending another $1400.00 to R&R the motor for a bad gasket.

Could be an intake manifold gasket to but either way, they screwed up.

How much money was saved by buying it online, and what is their warranty? Is there any danger of them going out of business in the near future? If you think so, maybe you can stick a fork in the whole deal and get one from another supplier.

I am almost certain is is only a head gasket or at worst a cracked head, however there was no over heating issues. The original motor seized up and we could not find a motor locally. We bought it online from what we thought was a reputable company. They are insisting we pull the motor and send it back for them to inspect. If I have to pull the motor out for a head gasket issue, I am going to try to get a full refund since the motor is not what they assured me it was, plus labor for the installation and removal, plus any costs involved in collecting. I am trying to find out if the two bolt main is the exact same as the four bolt. If it is not the same then we may have a foot to stand on.
Brad

[JimN]

Originally Posted by Brad B

I am almost certain is is only a head gasket or at worst a cracked head, however there was no over heating issues. The original motor seized up and we could not find a motor locally. We bought it online from what we thought was a reputable company. They are insisting we pull the motor and send it back for them to inspect. If I have to pull the motor out for a head gasket issue, I am going to try to get a full refund since the motor is not what they assured me it was, plus labor for the installation and removal, plus any costs involved in collecting. I am trying to find out if the two bolt main is the exact same as the four bolt. If it is not the same then we may have a foot to stand on.
Brad

If the two bolt was exactly the same, there would be no need to have a four bolt main.

Make sure your ducks are in a row before proceeding but you should be able to look online to find any technical info about why a 4 bolt would be used. I would start with some of the GM and GM sites and maybe even GM itself. Also, people like MYMC have built race motors, so he or a speed shop should be good for more info.

[Dave2302]

Originally Posted by Brad B

A local engine rebuilder claims a two bolt is just fine. Anybody know for sure?
Thanks Brad

Yep in your application a 2 bolt is fine. 4 bolts are only better in VERY high horespower / VERY high RPM applications and even then thats debateable. I know bespoke engine builders / tuners who reckon that in the real world a 2 bolt is actually stronger in certain applications.

The main point here is if your engine is filling with water be it a 2 bolt or 4 bolt, it is NFG

Did the motor come from the supplier all built up with heads and intake etc attached?
Or did the R&R guy have to install these. If you bought a "short" or a "3/4" motor it could be nothing to do with the builder, maybe a problem with intake manifold installation etc etc.

You need to properly diagnose exactly where the water is getting in before taking it up with the supplier, unless of course it was a fully assembled "crate motor". In which case send it back !!

HTH Dave