y-block running warm?
 

hi guys! finally have been able to enjoy driving the "rat".
after all she put me thru... anyway, I noticed she is running
a little hotter than before I rebuilt her. prior to rebuild it ran
180! now it's up to 210! the engine is basically stock, except
for "trips". std.bore. std.cam. it has an electric fan, comes on
205-210. radiator is new. i'am running a 180 thermo. anybody
have any thoughts? as always, I appreciate everyones replys!


richard

Re: y-block running warm?
 

Did you get the head gaskets on with front at the front?

Re: y-block running warm?
 

Yes sir! Forgot to mention my timing, 8 degrees initial. About 38 total.total. running 52 jets in the center carb.Plugs look good have a nice light tan color.

Re: y-block running warm?
 

since head gaskets were brought up, I just rememberd
I use "felpro". they recommend "cooling fix". drill 2-holes
in block, and 2- matching in head. I did this! this is the only
change I made in rebuild.

Re: y-block running warm?
 

Did you remove the freeze plugs and clean out the block? Pictures at the bottom of this linked page. The page was written for '55/'57 T-Birds but it generally applies to all Y-block engines.
There is a short list of common overheating causes.

https://www.ctci.org/gilsgarage/Overheating.php

.

Re: y-block running warm?
 

Yes sir! Freeze plugs removed hot tanked new cam bearings etc..myself, I'm leaning toward too much timing and not enough jetting?

Re: y-block running warm?
 

Just a thought, remove the thermostat and drive it. Maybe the thermostat is hanging up. What carb are you running 52 jets in?

Re: y-block running warm?
 

Ctr.carb #52. Out board #49

Re: y-block running warm?
 

It may be as simple as the engine being assembled as tight (close clearances) and may take a few miles to loosen up.

Maybe re-calibrate the fan(s) to come on sooner? If calibrated to cut in at 180 degrees or higher, it may be waiting too long to actually cool the coolant. Are the fans using a coolant temp or ambient air temp sensor to trip them? Do the fan(s) have a manual over-ride switch whereby you can cut them on earlier?


Do you have a TEMP GUN or are you relying on the OEM TEMP GAUGE?

Re: y-block running warm?
 

Temperature sending unit. To turn fan on its preset. I have dolphin gauges they're quite accurate.

Re: y-block running warm?
 

A coolant temp sensor, correct? Where did you mount it in the engine? Do your fan instructions describe installing a manual over-ride switch? Where is the GUAGE sensor located?

Re: y-block running warm?
 

Good move here (IMO)

Re: y-block running warm?
 

I did not install temp.sensor, came that
Way. It's front of manifold.

Re: y-block running warm?
 

OK...

The electric fan(s) came installed with your purchase of the car? The cooling systems functioned correctly before the rebuild and not now? The FAN COOLANT TEMP SENSOR is mounted in the intake manifold crossover in place of the heater control valve or elbow (depending on heater style)?

What degree THERM was installed before rebuild and is the replacement a full-flow style? Where is the TEMP GAUGE sender placed?

Re: y-block running warm?
 

Richard, you mentioned in post #6 about backing off on the timing. I wouldn't do that since more spark advance makes cooler exhaust temperatures. Retarding the timing from where it is now, will increase exhaust temps. This would only potentially cause it to run warmer than it is now.



Sal

Re: y-block running warm?
 

Great to hear from you sal! You
Always have good replies! What do think
Of jetting up CTR. Carb. To 54? The
Pics.of the is not very good..

Re: y-block running warm?
 

Your spark plugs sound like they are pretty ideal as far as color. 52 jets in the center carb should be good. Stock carbs had 50 or 51's (assuming they are Holley 94's).


If anything, if the power system is blocked off in the front and rear carbs, the jet size should be increased to about 54 or 55. I think you said they had 49 jets. However, if it runs well when the front and rear carbs open up, then maybe good the way it is.


Sal

Re: y-block running warm?
 

I had a '57 Bird with a heating problem. Turned out to be a reputed diaphragm in the vacuum advance unit. I picked up on it when I noticed that the power "pulsed" when driving about 35 MPH. Might consider it as a possibility.

Charlie Stephens

Re: y-block running warm?
 

I am running an MSD ready to run distributor with a vacuum advance... All three carburetors are the 94 models. The 2 out boards don't have any power valves in
Them. I am a little suspect, it's running a little to
Lean? The plugs do have some tan color but they look a little whitish to me.
Sal, do you have a pair of 54 Jets? I know you're quite knowledgeable with these old carburetors.
If you do,message me...

Re: y-block running warm?
 

I don't have any Holley jets that size but they are available on EBAY with free shipping for about $6 a pair. That's cheaper that you can get them from Holley or anywhere else I've seen. Pretty sure I sent you a link to an EBAY auction a little while back.


Sal