crate engines
Thread Starter
Tech Contributor
Joined: Aug 1999
Posts: 15,154
Likes: 3,959
From: Connecticut, USA
crate engines
I'm going against the grain here but I wanted to may you aware of some of what I found on a crate engine I just disassembled.
It's a 1980 350-250 4 bolt main long block that I purchased new from the local chevy dealership. I have 18k miles on it and it ran fine.
When we pulled the cam we found the front bearing was cracked and the cam journal oversize. The 2 aftermarket cams I had in the shop fit fine but the original one was very tight. We pulled the springs off the heads and found they used O ring seal on all valves, unbrella seals on the exhaust,and postive seals on the intakes. There was no way that baby was going to leak past the valves!!
The general condition was pretty good and we are now getting ready to fire it up with the new cam and bearing. I've heard of some problems with these engines over the years with cam and piston issues and was wondering if others heard of the same?
Gary
It's a 1980 350-250 4 bolt main long block that I purchased new from the local chevy dealership. I have 18k miles on it and it ran fine.
When we pulled the cam we found the front bearing was cracked and the cam journal oversize. The 2 aftermarket cams I had in the shop fit fine but the original one was very tight. We pulled the springs off the heads and found they used O ring seal on all valves, unbrella seals on the exhaust,and postive seals on the intakes. There was no way that baby was going to leak past the valves!!
The general condition was pretty good and we are now getting ready to fire it up with the new cam and bearing. I've heard of some problems with these engines over the years with cam and piston issues and was wondering if others heard of the same?Gary
Le Mans Master
Joined: Feb 1999
Posts: 6,807
Likes: 0
From: Hoosier
Cruise-In III Veteran
I have one of those 350 - 250 HP crates with about 30,000 miles on it now. Haven't had it apart though, because it's running great -considering it's only 250hp 
How deep into the block are the pistons on yours?
How deep into the block are the pistons on yours?
Thread Starter
Tech Contributor
Joined: Aug 1999
Posts: 15,154
Likes: 3,959
From: Connecticut, USA
About .030" I didn't bother checking with an indicator because this is a temporary engine for the Winter/Spring use.
This ran good too and that cam issue might not have caused anything to happen for a while. I had a earlier model,1978, that sucked up the nylon timing chain after 4,000 miles.
Gary
This ran good too and that cam issue might not have caused anything to happen for a while. I had a earlier model,1978, that sucked up the nylon timing chain after 4,000 miles.
Gary
Thread Starter
Tech Contributor
Joined: Aug 1999
Posts: 15,154
Likes: 3,959
From: Connecticut, USA
About .030" I didn't bother checking with an indicator because this is a temporary engine for the Winter/Spring use.
This ran good too and that cam issue might not have caused anything to happen for a while. I had a earlier model,1978, that sucked up the nylon timing chain after 4,000 miles.
Gary
This ran good too and that cam issue might not have caused anything to happen for a while. I had a earlier model,1978, that sucked up the nylon timing chain after 4,000 miles.
Gary
