Engine temp on chevy small block

Alright.. so what happens when it's at say 20deg advance...only reason I ask is because 1-2nd gear are a little slow but 3rd and 4th got the gitty-up..what gets a little more in the low gears
 
Chris142 said:
Sounds like either the balancer slipped or it has the wrong timing tab which is fairly common when mixing Chevy parts. I'd tune it by trial and error from here as the timing marks are obviously incorrect.
Click to expand...
It's silver tab with blue long bracket on top mounted to engine block. The weird thing is that at one point with the light the timing was at 22 and had 20"mercury on vacuum..when it's at 13 I got 15"mercury vacuum..and ran fine on both with no run on after shut off at 22deg advance. Dunno
 
Your centrifical advance is sticking. Your never going to get a timing set that remains consistent. Since the distributor is worn to the point of getting oil up inside and the centrifical advance is sticking you need a replacement. Dieseling at shut off can be from idling too high and or running too warm. Once you get a decent distributor, timing set correctly with live vacuum at the vacuum advance, overheating at idle solved, then you can fine tune the carb/idle. No need to touch the carb until then.
Edit: If your sticking with a conventional points distributor you really should invest in a dwell-tachometer. Points set at 30 degrees FIRST before timing set. Then carb adjustments last.
 
Last edited:
PontiacHO said:
Your centrifical advance is sticking. Your never going to get a timing set that remains consistent. Since the distributor is worn to the point of getting oil up inside and the centrifical advance is sticking you need a replacement. Dieseling at shut off can be from idling too high and or running too warm. Once you get a decent distributor, timing set correctly with live vacuum at the vacuum advance, overheating at idle solved, then you can fine tune the carb/idle. No need to touch the carb until then.
Edit: If your sticking with a conventional points distributor you really should invest in a dwell-tachometer. Points set at 30 degrees FIRST before timing set. Then carb adjustments last.
Click to expand...
That's why I recommended he upgrade to a Petronix electronic unit.
 
As others have indicated, you need a better fan. When you said that the temps return to normal driving down the road, it tells me you aren't getting enough air flow through the radiator at idle.

When I replaced the 307 in my 72 Nova with a 396, the guy at the speed shop recommended a heavy duty flex fan. I could feel the air from the fan standing behind the car (with the hood off). It never overheated in the hot, humid Florida summers, even with the wimpy 2 core radiator.
 
Wish I’d dialed into this thread sooner. I had a ‘57 with the 283. All the good stuff has been well covered here.

BUT I didn’t see this point mentioned. Do you know the compression ratio for this engine? I’m not sure it’s original based on modification to the radiator support where they’ve pushed it 3” forward. If it’s an original compression ratio, it will likely need premium fuel, especially with proper timing. In my experience, the 283, which was originally an engine calling for leaded fuel, it would easily experience preignition at temps above 140F. Advancing the timing made it worse, and until I figured it out had to run it a bit delayed. If you’re getting some popping, increase the octane while you get the settings dialed in.

these vehicles had a solid metal 4-blade fan with no clutch and no shroud. The fan-radiator gap was crude, about 1-1/2 inches if I remember. The idle rpm spec for the automatic was 450 rpm in gear (no kidding, I had the FSM). Iirc, the manual was a higher rpm, I think 550 if memory serves, at least with the 283.

and oh! These were not like the SBC’s of the 80s and beyond…. it was normal to heat up at idle. And the temp gauges were not buffered, so you’d see the real temperature swings that are hidden electronically in all modern vehicles. especially if the engine has finished a hill climb with heat built up, and then stopping, it’s harder to get it out and the needle would move from 40% to 65% on the gauge. So…. Some of what you’re seeing, to an extent, was period correct.
 
Last edited:
Carburetor1 said:
Any suggestions on best oil for this engine
Click to expand...
I typically run a Euro 0W-40 in my pushrod mills, but an HDEO like Delvac 1 5W-40 is also a great choice, and has a touch more phosphorous. I currently run D1 5W-40 in our boat, but its usage profile is a lot more demanding than your car. Tear-down results with M1 0W-40 in a few built Ford 302's showed impeccable cleanliness, so that's my recommendation, or Castrol 0W-40.
 
Didn’t we earlier say it was a 305, 307 or 350?

At some point you are going to want to dig deeper and try to figure out exactly what you have, the fact it pulls 20” vacuum tells me if the cam isn’t stock it is tiny.

I agree (again) with overkill on the oil.
 
Timing, read the plugs. Cut one open to view the porcelain to read mixture.

Cooling a classic car really needs to be with a re-cored radiator or a complete aluminum aftermarket one. A fan shroud is a must, and I'm a fan of electric fans.

The water jackets in an older engine will likely have a huge amount of sludge in them as well. I power washed my FE Ford engine when it was on the stand and got at least 2 cups of green/brown stuff out of the water jackets. And I had flushed the coolant prior the removing the engine to rebuild it.

Here is my cooling solution for parades and general slow drives. 10" Spals, the clearance in the middle is for the water pump pully. I cut the aluminum with a jig saw, and the holes are with a hole saw.
20210811_103152.jpg
20210811_151115.jpg
20211211_175525.jpg
 
Carburetor1 said:
Right now it's pulling 16" vacuum at 14degrees advance...put shell premium in and the car stopped dieseling after second start and starts every time. Napa Gold filter with Castrol 10w-40 conventional. Oil pressure at idle warm is 20 and 50 when driving
Click to expand...
(y) SHELL gasoline is good stuff. No magic cure all claims - just a quality fuel.
 
Carburetor1 said:
Right now it's pulling 16" vacuum at 14degrees advance...put shell premium in and the car stopped dieseling after second start and starts every time. Napa Gold filter with Castrol 10w-40 conventional. Oil pressure at idle warm is 20 and 50 when driving
Click to expand...
I am wondering why you are checking vacuum at 14 deg at Idle? It will be low. Did you see the timing bump up to well over 20 degrees with the vacuum advance hooked up to the correct port? - the one on the RIGHT facing the carb. I do not recall the vacuum port was verified to show a good vacuum. Also, the timing tab has to be verified for TDC given the discourse here. This car REALLY needs to go to a professional tune shop. It should not cost too much unless they are a ripoff.

ps.:, A lot of guys mess up their pertronix install, you need a 12v coil with internal resistor (or an HP coil) and the KEY RUN resistance wire needs to be eliminated. Alternatively you can go to a ballast on the firewall like a Chrysler product. Run 14 gauge stranded hookup wire at the smallest - this is high current low voltage.

Me? I will run the excellent DELCO-Remy type uniset points set and have an extra couple sets in the glovebox. Can fix any where - you wont get stranded with electrical-mechanical vs electronics. High performance over 1 HP per cube it's an L82 HEI, then MSD, then crank tigger as you climb the power ladder. -

Ken
 
Last edited:
You must log in or register to reply here.

Similar threads

dogememe
Small TGDI engine warmup/heat?
2
Replies
21
Views
2K
meep
I
Calif smog test results failed finally passed but don't understand NOX emissions
2
Replies
35
Views
2K
PandaBear
OM605
Driving without a fan
2
Replies
32
Views
2K
antonmnster
S
Oil leaks on Chevy LS engines
2
Replies
38
Views
1K
Snagglefoot
B
Did I destroy my engine?
Replies
17
Views
4K
bluesriderdf
Back
Top