Heating & timing

[Guest Lee Smith]

Can timing being off, befor/after, cause a engine to heat?

 

Background.

 

I just got the car. No history. eBay.

It is a 77 Corvette, but this is a dam good forum.

 

So far I am not impressed with it, but I had a 83 T.

At $x,xxx to $xxx, there is no comparsen.

I am going to finnish my 77 V8 this winter.

 

The speedo needs to read 90 to keep up with traffic doing 70.

The tack isn't working. I hope to get to it today.

With the speedo, up to 70, the temp is 180, at 90 - 210. .

The temp goes to 180 & stops rising at slower speeds, so the thermostat is working right.

5 to 10 miles at 90 the temp is 210 & does not get any higher.

Getting off the interstate, on the 55 roads, the temp drops to 180 in about 5 miles.

The car pissed when I did, at a rest stop, without the 5 miles on 55 roads.

It may have been over full. It is at the right level now.

 

There is a new looking 1 core radiator in the car. Is it big enough, or do I need a 3 core?

 

I checked the timing yesterday. It was about TDC, or later. It is now 10 before. ??

 

Any thoughts on the above will be appreciated.

 

Lee Smith

[Guest Nic-Rebel450CA]

The speedo needs to read 90 to keep up with traffic doing 70

 

Is it geared crazy, or do you have an automatic transmission that is about toasted? I'd look at this first.

 

Yes, if your timing is off either direction too far then it can cause heat. Too advanced and it will ping, too delayed and you could get detonation. It should definately be firing BTDC, make sure that the timing arrow is accurate too. Someone might have put it on wrong. Take your distributor cap off and manually crank the engine with a large wrench. (easier if the spark plugs are out). Turn the engine until the distributor is lined up just barely starting to point to the lead for the wire for the plug for cylinder 1 and then check your timing mark and arrow to see where they sit. If it's not very close then the arrow and/or balancer may not be lined up right (not necessarily a problem, just makes it a PITA to time).

 

You can also try adjusting the timing by ear, just advance it until it just starts pinging and then turn it back. Go for a drive and floor it at low RPMs and see if it pings, if it does, retard the timing a little more.

[Guest Lee Smith]

I think that a PO played with the gearing.

 

I have driven AT cars wuth shot ATs befor & this 1 does not slip.

 

First I set by timing light.

Then advanced a bit more, like I did befor I had a timing light & backed off a bit.

I was wondering if 10 BTDC was correct. ??

10 BTDC is where it runs very good.

 

The new 1 core's seem SLIM to me. I am use to 3 & 4 copper. ??

 

Thanks for the input. I will try to get a 10 mile test drive in this week.

 

Lee

[Guest Z-rific]

10 degrees of advance at idle is a pretty safe reading. It should crank easily and run well at this setting. I also don't believe that 10 degrees is enough advance to make the car run unusually hot.

 

I would start looking through the cooling system. Since the car is new to you, you can perform some maintenance procedures to gain confidence in the setup.

 

I would first look into the "stock" cooling setup for this particular model and year. If it came with a larger radiator, then start there. If the radiator that is on it is stock, start looking elsewhere.

 

Flush the system. Check the thermostat and make sure it isn't sticking. Check all hoses and clamps.

 

Do a search here for posts about cooling problems. You will find a ton of info which may help you diagnose the problem. Do the hoses have springs in them? These keep the hoses from collapsing under higher pressure.

 

Good luck and keep us posted.

[Guest Lee Smith]

Thanks all.

 

Everything seemes to check out ok.

I will know if I get a 10 mile drive in this week ot interstate speed.

 

Lee

[baddriver]

The temperatures you are reading do not seem excesive to me. If it lost some coolant when it was hot, I would look closely at the water pump weep hole. A lot of times these things leak a little when the cooling system is under pressure, but don't leak at any other times. Even if the cooling system is working fine, the engine will heat up after you shut it off, and this can cause pressure in the cooling system, resulting in coolant loss. Does it have an overflow tank?

 

cooling capacity is a combination of the surface area of the radiator and the rate that air flows through it. Single cores often let a lot more air through, and can cool just as well as a thicker radiator. I wouldn't be too quick to blame the radiator, unless you find that it's plugged.

 

Have fun, and watch out for the state troopers when you go tearing down I35.