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Started rebuilt engine over heated lots of questions
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Author:  oklahoma joe [ Fri Jan 01, 2010 8:04 am ]
Post subject:  Started rebuilt engine over heated lots of questions
Happy new year!

Started my engine yesterday. :D and it made some nice noise sounded pretty health for first start with out tuning. :D :D

But then It started to get hot. :evil: hope I did not destroy anything. :oops:

over heat long video

http://www.youtube.com/watch?v=9qqRUCbQHMk

After timing adjustment and removing thermostat

http://www.youtube.com/watch?v=YE2uyBi6LmM

I ran it for about 15 minutes at 2000 to 3000 rpm which caused the temp to get to about 230 to 240 and a fountain of coolant then steam came out the over flow tube. Then I shut it down.

I removed the 195 degree thermostat and set the timing ignition to 5 Degrees before TDC with vacuum disconnected at 1200 rpm. But I did not run it for long because I did not know what was going on with the cooling problem. I've heard that a engine may run hot when it is being broken in??? But I have never had this problem before starting a new engine. So I am at a bit of a loss. The radiator could be suspect. I did not have it cleaned.

The compression is about 8.6:1.

Oil pressure stayed above 45 psi the whole time.

Vacuum was rock steady but low at idle around 5-10 in hg and 15 in hg 2000 - 3000 rpm.

The cam is a bit retarded about 2 degrees (may be advancing it if I can't smooth out Idle)

So any suggestions on how track down the extra heat. Or should I just try again after getting the radiator cleaned.

Joe
Author:  SlantSixDan [ Fri Jan 01, 2010 8:21 am ]
Post subject: 
If the radiator is clogged, it won't work.

5° base timing at 1200 rpm is too retarded. The base timing is to be set at idle (650 to 800 rpm depending on engine configuration).

What was the goal of removing the thermostat?
Author:  DusterIdiot [ Fri Jan 01, 2010 8:48 am ]
Post subject:  Burp...
If you didn't slowly fill the coolant and let the engine/head work out any trapped air, it will get hot, then "puke"... some people have cheated and used a temp t-stat with a hole drilled in it to bypass the mechanism and bleed any air, then after break in, swap out to a normal stat. I know some V-8 builders swear by running a garden hose into the radiator and doing break in that way, I've never had a problem as long as you fill the cooling system slowly and carefully letting the air work it's way out before capping the radiator.

-D.Idiot
Author:  hantayo13 [ Fri Jan 01, 2010 9:58 am ]
Post subject: 
i always drill 1/8 inch hole about 12 oclock in thermostat...dont hurt nothing and lets air out of system
Author:  6shotvanner [ Fri Jan 01, 2010 10:02 am ]
Post subject: 
Joe bring me up to speed here,was the rig running before the rebuild and was there a problem with the rad then? If it was ok before then it's more then like as mentioned above by Dan and Rob. I might catch a little flack here but I have always left the rad cap off on first fire-up.Even filling the system slowly there usually is a few 'air pockets' and when the Tstat opens the cooling system is suddenly down on fluid. It's a busy time on first-fire but keeping an eye on the rad level when I see it drop(usually suddenly) in goes more coolant until she's full,infact I'm usually flittin about during this time with a coolant jug in my hand waiting for it to happen.When breakin is done I let everything cool down(including myself)then put the rad cap on and go from there.Haven't lost one(yet)in 45 years that way 8)
Author:  DusterIdiot [ Fri Jan 01, 2010 12:58 pm ]
Post subject:  No Flack.
Quote:
I might catch a little flack here but I have always left the rad cap off on first fire-up.Even filling the system slowly there usually is a few 'air pockets' and when the Tstat opens the cooling system is suddenly down on fluid.
Can't dispute that, it's good advice.
Author:  oklahoma joe [ Fri Jan 01, 2010 6:04 pm ]
Post subject: 
Quote:
If the radiator is clogged, it won't work.

5° base timing at 1200 rpm is too retarded. The base timing is to be set at idle (650 to 800 rpm depending on engine configuration).

What was the goal of removing the thermostat?
The temp was kind of erratic, would raise and lower raises and lower. So I thought the new thermostat may be sticking. So I removed it to see if it made a difference. Will check this one one the stove in some water and see if it is working properly. I guess it was a heat of the moment decision. :lol:
I set the ignition timing a bit retarded because an advanced timing can lead to extra heat and I was trying to reduce heat as much as possible.

Joe
Author:  oklahoma joe [ Fri Jan 01, 2010 6:18 pm ]
Post subject: 
Quote:
Joe bring me up to speed here,was the rig running before the rebuild and was there a problem with the rad then? If it was ok before then it's more then like as mentioned above by Dan and Rob. I might catch a little flack here but I have always left the rad cap off on first fire-up.Even filling the system slowly there usually is a few 'air pockets' and when the Tstat opens the cooling system is suddenly down on fluid. It's a busy time on first-fire but keeping an eye on the rad level when I see it drop(usually suddenly) in goes more coolant until she's full,infact I'm usually flittin about during this time with a coolant jug in my hand waiting for it to happen.When breakin is done I let everything cool down(including myself)then put the rad cap on and go from there.Haven't lost one(yet)in 45 years that way 8)
Thanks

I started the car when I got it two years ago and ran it for about 30 minutes with no problems. But the radiator had sat for a long time maybe 10 years? I put a garden hose in the radiator before I put it back in the car and it seemed to flow free. But when I started the engine some brown junk floated to the top and I did not see the swirl of coolant that you normally see after the thermostat is open.
On my other engines I has rebuilt start up goes just as you explained it. But this is the first time with solid lifters so I kept the rpms up higher then I had before. I think I will try drilling a hole in the thermostat and try again.

Thanks Joe

:)
Author:  oklahoma joe [ Fri Jan 01, 2010 6:21 pm ]
Post subject: 
Quote:
i always drill 1/8 inch hole about 12 oclock in thermostat...dont hurt nothing and lets air out of system

Thanks I will try it. Boy, if I just don't know how to put in engine coolant will I be happy.

Joe
Author:  66aCUDA [ Sat Jan 02, 2010 8:52 am ]
Post subject: 
Joe
What I have seen is that the machine shop doesnt get the chunks and rust out of the water jacket. This will instantly clog your rad on start-up. To avoid this I run the engine on a hose and 5 gal bucket. This allows the junk to come out and go to the bucket and not clog the rad up.
There is also a filter that can be made to trap the stuff in line. It was posted on here about 2 years ago. I think it was from a Mercedes forum.
Frank
Author:  SlantSixDan [ Sat Jan 02, 2010 2:55 pm ]
Post subject: 
I put a coolant filter in my '73 just recently. I looked at the Gano unit, but decided to get the Tefba filter instead, because it can very easily be serviced (cleaned) without draining the cooling system, removing any hoses, or making a mess.
Author:  oklahoma joe [ Wed Jan 06, 2010 6:05 pm ]
Post subject: 
Cleaned out the radiator checked for good flow and drilled a hole in the thermostat and put at 12:00 position. It worked no steam no puking radiators. Temp just sat between 175 and 180. Set idle and all is well.

Thanks for the advise.

Joe
Author:  66aCUDA [ Thu Jan 07, 2010 7:22 am ]
Post subject: 
Cool glad to here it.
BTW I have the trim and stuff off the cuda so send me a list and I will let you know,via PM.
Frank
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