Starting my engine build

[davepl]

Originally Posted by Mrturner1

I just had a gut wrenching thought...what if it's a head gasket.

Nah, that'd suck, but it's only time (and gaskets), not the end of the world.

When it's cold, start it up and look into the filler neck of the rad (obviously don't take the cap off a hot or warm engine). If you see a steady stream of new bubbles, almost foamy, then I'd worry.

You'd need a leakdown tester to know for sure, a compression test won't find anything but a huge leak.

With a leakdown tester you'd hear the air with your stethoscope in the radiator, meaning combustion -> coolant leak.

That's your worst case. Odds are its something simpler.

I assume you followed proper torque sequence and pattern and all of that when torquing down the heads? Do you gaskets require a re-torque? Some types do, some don't.

[geezer#99]

Originally Posted by davepl

Gotta disagree on this, it's an old wives tale that coolant needs to somehow "linger" in the radiator. No restriction or t-stat is required for cooling, only for proper warmup and operation. It's not worth an argument unless someone is genuinely curious, but increasing the t-stat set point won't help it run cooler.

Experiment with an orifice plate and then tell me retention time is not important.

[Mrturner1]

Originally Posted by davepl

Nah, that'd suck, but it's only time (and gaskets), not the end of the world.

When it's cold, start it up and look into the filler neck of the rad (obviously don't take the cap off a hot or warm engine). If you see a steady stream of new bubbles, almost foamy, then I'd worry.

You'd need a leakdown tester to know for sure, a compression test won't find anything but a huge leak.

With a leakdown tester you'd hear the air with your stethoscope in the radiator, meaning combustion -> coolant leak.

That's your worst case. Odds are its something simpler.

I assume you followed proper torque sequence and pattern and all of that when torquing down the heads? Do you gaskets require a re-torque? Some types do, some don't.

Yep followed all the torque specs and sequence and made 3 separate go around a to get to required torque rating. I don't know if the gaskets require a re-torque or not, they are FelPro .039's

Definetly going to look for bubbles tomarrow thanks for jumping in Dave

[Mrturner1]

I really think the old radiator is contributing, and from what I'm reading an overflow tank is really important for not getting air into the system, and for proper burping of air already in the system

[BrianG]

My gut tells me it's those electric fans. The right shroud, a clutch and a fan really wouldn't be all that much with what you already have into this. Could always try to sell the electrics on CL or something. You hear much less people who have had issues with the correct clutch fan setup cooling properly compared to those who have had issues trying to get electrics to work correctly on these old trucks. I have an old radiator, no overflow tank, 35 inch tires, a 4x4 and have worked it hard off road with a stock shroud and fan. It don't overheat and I don't have to even wonder if the fan is going to come on. It works because that's how the truck was designed to work. ........ Okay sorry to come back to this again, but please at least consider that the fans might not be the best setup for your cooling system.

[Mrturner1]

Originally Posted by BrianG

My gut tells me it's those electric fans. The right shroud, a clutch and a fan really wouldn't be all that much with what you already have into this. Could always try to sell the electrics on CL or something. You hear much less people who have had issues with the correct clutch fan setup cooling properly compared to those who have had issues trying to get electrics to work correctly on these old trucks. I have an old radiator, no overflow tank, 35 inch tires, a 4x4 and have worked it hard off road with a stock shroud and fan. It don't overheat and I don't have to even wonder if the fan is going to come on. It works because that's how the truck was designed to work. ........ Okay sorry to come back to this again, but please at least consider that the fans might not be the best setup for your cooling system.

Well I'm staying open minded, but I don't see how a mechanical fan could cool as well as dual 2500 cfm electrics while at idle. BUT, I don't know what cfm a clutch fan pulls at idle so I can't make an educated argument about that. I'm gonna be bummed if my fan setup isn't sufficient, but, whatever it takes to make it work

[68c10owner]

Originally Posted by Mrturner1

I really think the old radiator is contributing, and from what I'm reading an overflow tank is really important for not getting air into the system, and for proper burping of air already in the system

A over flow tank just catches the coolant so it doesnt go onto the ground. It wont do anything any different to get air out of the system than just dumping it.

Originally Posted by Mrturner1

Well I'm staying open minded, but I don't see how a mechanical fan could cool as well as dual 2500 cfm electrics while at idle. BUT, I don't know what cfm a clutch fan pulls at idle so I can't make an educated argument about that. I'm gonna be bummed if my fan setup isn't sufficient, but, whatever it takes to make it work

Doesnt sound very open minded to me. I know you think they should be better because they were expensive and have a high cfm rating but how are they working out for you? All you changed was the fans. THat radiator is up to the task now if it was before. And with as much as you have been running it you should have all the air from the system by now.

[Mrturner1]

Originally Posted by 68c10owner

A over flow tank just catches the coolant so it doesnt go onto the ground. It wont do anything any different to get air out of the system than just dumping it.



Doesnt sound very open minded to me. I know you think they should be better because they were expensive and have a high cfm rating but how are they working out for you? All you changed was the fans. THat radiator is up to the task now if it was before. And with as much as you have been running it you should have all the air from the system by now.

When I lived in Rocklin (30 miles downhill) in an apartment I started pulling apart the stock shroud and clutch fan and had to make a quick move to where I live now I grabbed a 16" single Flexalite just to make the trip up to the new house. No shroud, just a single electric fan that pulled maybe 1600 cfm and it never got over 185* going from 800 ft elevation to 4000ft and it was 75* outside. That 16" fan was just a band aid to get my truck to the new house and everything ran great and cool.

The fans I have now can suck a shop towel to the front of the radiator no problem, which is why I'm so headstrong about my fans being sufficient. I don't think because they are expensive that they will automatically work, but I do think they pull enough air because a single 16" with no shroud kept it cool going up a mountain.

I DID change the thermostat during the build from a 190 to a 160, so that's definetly something I'll try. If the problem is the electric fans I'm certainly going to change to a mechanical, but it just doesn't make sense to me considering the trip to the new house and that it never got hot during break-in which was a constant 2300rpms in my garage for 20 minutes, know what I mean? It stayed cool during high rpm break in, and that gives me a terrible feeling that it's a head gasket OR, and I'm hoping you can clarify, maybe a leak in the carb base gasket or intake?? What do you think?

[68c10owner]

Originally Posted by Mrturner1

When I lived in Rocklin (30 miles downhill) in an apartment I started pulling apart the stock shroud and clutch fan and had to make a quick move to where I live now I grabbed a 16" single Flexalite just to make the trip up to the new house. No shroud, just a single electric fan that pulled maybe 1600 cfm and it never got over 185* going from 800 ft elevation to 4000ft and it was 75* outside. That 16" fan was just a band aid to get my truck to the new house and everything ran great and cool.

The fans I have now can suck a shop towel to the front of the radiator no problem, which is why I'm so headstrong about my fans being sufficient. I don't think because they are expensive that they will automatically work, but I do think they pull enough air because a single 16" with no shroud kept it cool going up a mountain.

I DID change the thermostat during the build from a 190 to a 160, so that's definetly something I'll try. If the problem is the electric fans I'm certainly going to change to a mechanical, but it just doesn't make sense to me considering the trip to the new house and that it never got hot during break-in which was a constant 2300rpms in my garage for 20 minutes, know what I mean? It stayed cool during high rpm break in, and that gives me a terrible feeling that it's a head gasket OR, and I'm hoping you can clarify, maybe a leak in the carb base gasket or intake?? What do you think?

What does your oil look like? Any milk? You can pressure test the cooling system and that will tell you if something is failing. Still have that single? Try it out again and see what happens. Are the new fans pushers or pullers?

You can try a higher t-stat but I wouldnt bet the farm that its going to fix your problem.

[Mrturner1]

Another thing that was mentioned was re-torquing everything after a few heat cycles, I haven't done that yet. IF there is a leak somewhere that is gasket related, can that be fixed by torquing everything down again or is that wishful thinking lol?

68c10owner thank you for all the help man, I hope I'm not sounding arrogant about the electric fan thing. I appreciate you checkin in so often and helping

[Mrturner1]

Haven't looked at the oil yet but I'll pull the stick right now and take a look. Fingers crossed

[68c10owner]

Originally Posted by Mrturner1

Another thing that was mentioned was re-torquing everything after a few heat cycles, I haven't done that yet. IF there is a leak somewhere that is gasket related, can that be fixed by torquing everything down again or is that wishful thinking lol?

68c10owner thank you for all the help man, I hope I'm not sounding arrogant about the electric fan thing. I appreciate you checkin in so often and helping

I have never retorqued iron heads afterwards. Aluminum, yes but never iron and never had a issue. Did you put thread sealer on the threads? Many of the head bolts go into the water jacket. Did you use a thin film of sealer around the water ports on the intake? If you had a blown head gasket you would either have milkey oil or be burning coolant and you would smell it.

I dont think you are sounding arrogant about the fans. you are fairly new and learning a lot. The best lesson I`ve learned is listen to experience. There are several of us offering advice and several of us have questioned the fans. I`m not saying that they are the problem but you have to think about things like this, was it working before? Yes? Ok, what was changed? Then you try to prove or disprove that the fans are causing the problem. It`s just like finishing one project before you start another. You can ask us all the questions you want but you still have to follow through. You want to trust the fans, ok. Try the t-stat. If that fixes your issue problem solved. but if it doesnt then where do you go? Maybe a bad water pump. I`ve seen new ones fail. After that there isnt much else to rule out.

[Mrturner1]

Originally Posted by 68c10owner

I have never retorqued iron heads afterwards. Aluminum, yes but never iron and never had a issue. Did you put thread sealer on the threads? Many of the head bolts go into the water jacket. Did you use a thin film of sealer around the water ports on the intake? If you had a blown head gasket you would either have milkey oil or be burning coolant and you would smell it.

I dont think you are sounding arrogant about the fans. you are fairly new and learning a lot. The best lesson I`ve learned is listen to experience. There are several of us offering advice and several of us have questioned the fans. I`m not saying that they are the problem but you have to think about things like this, was it working before? Yes? Ok, what was changed? Then you try to prove or disprove that the fans are causing the problem. It`s just like finishing one project before you start another. You can ask us all the questions you want but you still have to follow through. You want to trust the fans, ok. Try the t-stat. If that fixes your issue problem solved. but if it doesnt then where do you go? Maybe a bad water pump. I`ve seen new ones fail. After that there isnt much else to rule out.

I used a new set of fel pro head bolts that came with sealant on them, but I can't remember if I used sealant on the intake bolts. I just checked the oil and it looks great. No milky, just clean oily goodness.

The fact that a few of you are mentioning the electric fans is what concerns me lol I trust you guys experience and I also really like my fans. It's silly but it's the same deal as the big cam, ALWAYS wanted one when I was a kid, just sounds cool and stands out from other trucks. Electric fans just make it feel more like a cool race truck I suppose

[68c10owner]

Originally Posted by Mrturner1

I used a new set of fel pro head bolts that came with sealant on them, but I can't remember if I used sealant on the intake bolts. I just checked the oil and it looks great. No milky, just clean oily goodness.

The fact that a few of you are mentioning the electric fans is what concerns me lol I trust you guys experience and I also really like my fans. It's silly but it's the same deal as the big cam, ALWAYS wanted one when I was a kid, just sounds cool and stands out from other trucks. Electric fans just make it feel more like a cool race truck I suppose

Again, the fans may not be the issue but since your cooling issue didnt start until after you installed them thats where I would start. Everytime I removed the stock set up and went to even a flex fan my engines would run a little hotter. Some heat isnt bad, and 210 sitting idle is fairly normal. What is it driving down the road? does it run cooler? Stay the same? get hotter?

[Mrturner1]

I have a feeling that tomarrow this running hot issue is going to go away if I play with the timing a little. I've read a lot and it seems simple, but timing is something I'm brand new at so it seems like a logical place to look for a mistake.

[Mrturner1]

Originally Posted by 68c10owner

Again, the fans may not be the issue but since your cooling issue didnt start until after you installed them thats where I would start. Everytime I removed the stock set up and went to even a flex fan my engines would run a little hotter. Some heat isnt bad, and 210 sitting idle is fairly normal. What is it driving down the road? does it run cooler? Stay the same? get hotter?

Driving it was more like 200* but then it would blow a little coolant out and then a little more until it started climbing again in temp. It was at 180-185 during break in a couple days ago

[68c10owner]

Originally Posted by Mrturner1

I have a feeling that tomarrow this running hot issue is going to go away if I play with the timing a little. I've read a lot and it seems simple, but timing is something I'm brand new at so it seems like a logical place to look for a mistake.

(Palm to forehead) Dude, 34 total and 14 initial is fine. It is not causing your heating issue if that is what your timing actually is.

[swamp rat]

Originally Posted by davepl

Gotta disagree on this, it's an old wives tale that coolant needs to somehow "linger" in the radiator. No restriction or t-stat is required for cooling, only for proper warmup and operation. It's not worth an argument unless someone is genuinely curious, but increasing the t-stat set point won't help it run cooler.

I agree with Dave on this, the thermostat temp is only the opening temp that allows circulation, the temp reached is a direct relation to engine load and heat generated, the cooling system and the amount of airflow thru the radiator .. That said i usually run a 180 or a 190

I personally think its the lack of the shroud channeling the air to the front of the engine.

But where is your temp sensor installed? in the driver side head? or on the water pump? or intake?

[Mrturner1]

Originally Posted by swamp rat

I agree with Dave on this, the thermostat temp is only the opening temp that allows circulation, the temp reached is a direct relation to engine load and heat generated, the cooling system and the amount of airflow thru the radiator .. That said i usually run a 180 or a 190

I personally think its the lack of the shroud channeling the air to the front of the engine.

But where is your temp sensor installed? in the driver side head? or on the water pump? or intake?

Temp sensor is in passenger side head

[Mrturner1]

During cam break in it ran nice and cool. That's high rpm in a garage with no fresh air, same setup I have now for cooling. That's the part I don't get

[SnS C10]

When your in the garage during break in there is no real load on the engine. The temps should not rise to an unsafe level if everything is working correctly. Now, when you put it in gear and drive it, there is much more strain on the engine, its working to pull a truck around, and that's when your noticing the temp go up.

You need to start eliminating things here....it sounds like its running good which means, timing is ok, carb is adjusted, no intake or exhaust leaks. Start eliminating now. I have never run a 160 thermostat. Always around a 195 or no thermostat at all. Maybe your thermostat is getting stuck closed, I have had this happen before, on a brand new part. You can always remove it completely and check the temp again. If its fixed at that point, its thermostat. If not, pull the fans

I know a lot of guys who have trouble cooling their engines when using fans with no shroud. Always hear the stock setup with shroud is extremely efficient even on higher horsepower engines

[BrianG]

A possible reason as to why the electrics "MAY" (and I'm not positively saying they are) not be cooling effectively, could be air flow around and through the vehicle at highway speeds. without putting it in a wind tunnel, with cameras inside and around the vehicle, it kind of hard to say what's going on in there. There could be some high positive or negative pressures being created. The fans may be 'capable' of moving so many cubic feet of air per minute, but if there isn't any air there, due to negative pressure zones in front of it, then it might just be spinning doing nothing, or little. That's why I say, the system is designed to work a certain way, With a fan shroud. Just by removing the shroud, it could have changed the air flow dynamics inside and around the vehicle/radiator/engine. I say all of this, just as a 'possible' explanation as to why those fans, which theoretically should cool it just fine, might not being working effectively. Again, without a fancy wind tunnel, this is just a theory.

[SnS C10]

briang that also explains why it was staying cool in the garage as the fans are able to work without being affected by the wind. Get a shroud on that thing in my opinion

[Mrturner1]

Originally Posted by SnS C10

briang that also explains why it was staying cool in the garage as the fans are able to work without being affected by the wind. Get a shroud on that thing in my opinion

It's getting hot sitting in the garage, in the driveway, or driving it. The first time I actually got to take it out and drive it, and I pushed it hard a couple times, it never went over 180 while driving or at an idle. Something failed from the time I drove it the very first time and when I parked it that day because the timing was adjusting itself due to a dork move on my part not tightening the distributor

[SnS C10]

start with the basics. check bolts, timing, adjust carb. if it heats up, check, remove, or replace thermostat. If it still heats up, try a stock fan and shroud