[70camino]

I have a 1965 283 Chevy engine that seems to run pretty good. I haven't actually driven the car, but ran the motor before starting to take the car apart for a body off restoration. I know that driving the car for a while would have told me a lot, but the reason I didn't drive it was that I bought it this winter, there is snow on the ground, and it does not have license plates.

Compression is as follows: four cylinders at 120 psi, one at 130 psi, one at 115, and two about 105 to 110 psi. The engine isn't making any major bad noises. I have no idea if it burns oil or not, but it isn't blowing huge clouds of smoke. The spark plugs are old and looked fairly even in color and wear. None were gunked up with heavy deposits or oil. The car spent about the last 12 years parked, although it was occasionally run for short periods of time.

Does anyone konw what the original factory compression should be on a low horse, two barrel 1965 283?

Before putting this car back together again, assuming the project makes it that far, would it be recommended to disassemble and rebuild the engine?

Although I might have to post a transmission question in another forum, I'm wondering if the Powerglide should come apart before reinstalling it. Again, I have no idea whether it is good or not. Any clues on how to tell if it needs a rebuild without driving the car?

Thanks for your advice,
David

1970 El Camino SS396
and a few projects

 

[Unclepennybags]

David,

Was the engine hot and the throttle fully open when you did the compression test? The numbers do look low to me. Seems like my 1964 Chevrolet Service manual said 150 and each cylinder within 20 of the others. Of course, if the engine has had a different cam installed that will affect your numbers also.

If the plugs came out clean like you said, and the engine doesn't smoke you can get another season or two out of it. If you want to do everything now, or need to depend on the car, pull the engine and rebuild it. If you can do things in stages, finish the body aspect of the project and do the engine next winter.

If the Glide goes into gear quickly and firmly forward and reverse, and doesn't leak, let it go. On the other hand, if you are inclined to do everything at one time, yank the engine and trans and you'll have a fresh dependable drivetrain.

Mike

 

[SWHEATON]

If you did the compression test correctly as Mike stated above and those are the true comp reading if you have the time & money i would rbld it. But,if money & time is tight i bet you could get buy for a while since it does not smoke yet or make any knocking noise at this point as long as you go easy on it and dont plan on putting on a lot of cruise miles. But a rbld would still be lurking in the near future so if at all possible do it now.

If this would be stock rbld non perf motor and the bores are ok you could get away fairly cheap with a hot tank,hone of std bore,cast iron rings to ensure a good seal on old bores,new bearings/cam bearings,oil pump,cam/lifters,chain/gear,and a std valve job. Even if you bored it low perf cast pistons are cheap so if it were me i would opt for at least .030 over on the tired 40 yr old 283.

 

[Guest]

Seem to recall that the old 195hp/283 two barrel motor was like 9.5 to 1 CR.

I will check when I get home and if I don't post back, it is!!

pdq67

Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

 

[dsr]

If it runs and doesn't smoke "drive it" you have nothing to lose. It's not a big deal to change out the motor later if turns out to be no good. In the mean time you may get a few years out of it. I have bought many used junk yard motors over the years, if it runs quiet, smooth and no smoke your good to go. Dave

 

[70camino]

Thanks. I realized later that the motor should have been warm and the throttle and choke open. The motor was cold and the throttle and choke were closed. Would that cause a low compression reading?

I probably can still restart the engine to warm it up. If so, maybe I should redo the compression test. What do you think.
David

 

[Mike Feudo]

I think the 65 283s had 8to1 the later ones used the 4bbl heads for 9to1. It doesn't look that bad.

 

[Unclepennybags]

Originally posted by 70camino:
Thanks. I realized later that the motor should have been warm and the throttle and choke open. The motor was cold and the throttle and choke were closed. Would that cause a low compression reading?

Without a doubt.

Originally posted by 70camino:
I probably can still restart the engine to warm it up. If so, maybe I should redo the compression test. What do you think.
David

Definately re do the compression test. Warm it up fully, and try to do the test while the engine is still hot.

Mike

 

[70camino]

Well, I warmed up the engine and retested the compression with the choke and throttle open. The readings went up a little and also became more consistent.
Three cylinders came in at about 122 psi, another three at about 127, and two around 135. That makes for a variation of about 10%. Possibly that isn't too far off what this engine should be at??
David

 

[Unclepennybags]

That's much better. (I have to check my shop manual, but I think that the spec is 150. Decent chance though if you are running a non-stock cam that your numbers will be lower, worn timing chain will do that also.) So, you are a little low, but all your cylinders are now fairly close which is a good sign.

It's likely you can get several seasons out of that engine. You can put off rebuilding it for a while if project funding is short in any way.

Mike