Ok Here it goes again.

I think this Censored truck is still using coolant.

When I start the motor cold it takes a couple of tries but starts with what I would think would be a reasonable amount of effort.

The problem is when I look into the radiator when the engine is cold I see the fluid pulsating and after about 30sec of run time bubbles come out. I let it run for a couple of minuets and the bubbles were still there. The bubbles are small a little smaller than a pea and one two or three of them come up every second or so. It seams pretty consistent. The pulse of the fluid seams to be in tune with the rattle of the engine. When I filled the engine with coolant I took the heater core feed hose off to let air out of the block and put it back on when coolant came out of it and preceded to fill it up.

I could not see this before because the heater core return was routed to the water pump. Now that it is back where it belongs (just below the radiator cap) I can see the bubbles.

Does this sound like I definitely have trouble in the head / head gasket area?

I can get a compression tester from Harbor Freight for $20 should I check the integrity of the engine before doing anything?

My oil pressure is also lower than the old engine. I am using the same pressure sender and I get 35lbs at highway speed where I used to get about 50lbs.

Edit: P.S. Since I fixed the coolant leak I have only driven the truck 12 miles. Am I just being a hypochondriac with this truck?

It never ends... :eek:

Well, that definitely sounds like a head gasket. :(

I think that if I were you I would drive it a little more and see what happens before changing the head gaskets...

Tell me about it.

I am begining to hate this truck even if it was my dads.

My dad passed away 1 year ago. Maybe he is telling me something.

I am pretty sure my 91 heads are good. they have 300K miles on them so they will need a valve job. Will they fit on the 83 block?

My dad passed away 1 year ago.

I'm sorry to hear that... :(

I am pretty sure my 91 heads are good. they have 300K miles on them so they will need a valve job. Will they fit on the 83 block?


I think the heads would fit fine, but it is probably just a simple head gasket problem that has nothing to do with the cylinder heads themselves... :)

My thought was I heard the later (91) heads were stronger resisted cracking and the coolant leakage thing was fixed.

Also they would match my 91 IP.

.

Edit: P.S. Since I fixed the coolant leak I have only driven the truck 12 miles. Am I just being a hypochondriac with this truck?


12 miles is not far .wait for a while before you do something.

I just replace my IP and when i fire it up it bubble in the rad and even get hotter on the gauge than usual for 50-75 miles than everything settle down and it fattle like a champ;) , , , again

Now i will pull out my electronic temp gauge that i install to track the real temp on the engine

Ed

Thank you

I just went for a 25 mile drive I will see if is used any coolant. I will run to town and back a couple of time as well before I get to excited.

Usually the sure bet sign of blown head gaskets is the overflow tank getting over full or bubbles in it, meaning that pressure in the coolant has exceeded the pressure cap on the radiator. Small bubbles in the coolant after the engine is fully warmed up can mean that the head gaskets are starting to go bad, minor leak.

Well after my drive I checked the overflow tank and the level had not risen at all. however this morning I checked it after if had fully cooled and the level in the overflow tank had dropped about 1/2". The radiator is still full. I have not really looked hard for bubbles in the overflow tank but I will check that.

Just keep driving it. Don't go crazy about it... Until you have put a good number of miles on it you won't know for sure what it is going to do.

Just keep driving it. Don't go crazy about it... Until you have put a good number of miles on it you won't know for sure what it is going to do.

Will do.

I do have that set of 91 heads though are they worth hanging on to? Are the 91 heads better than the 83 heads? I do have injector lines for 91 heads so that is not a problem.

Keep the '91 heads... You might end up needing them. A good set of heads without cracks is expensive and rather difficult to find. They are probably better than '83 heads, but that isn't really the reason you would be keeping them... Keep them because they aren't cracked. You could end up needing a cylinder head and a good set of heads without cracks is expensive...

On a 91 the thermostat is vertical. I took the thermostat housing off and the thermostat out and the belt off (no water circulation). I started the truck and looked for bubbles. There were none. Well I should not say none there were some tiny ones about the size of the bubbles that are inside of you glass of Sprite or Mountain Dew. and they were not consistent. There were a few of them at the beginning and that was all. I am sure these were just the bubbles stuck to the casting.

I ran the truck for less than a minuet the first time, 1.5 minuets the second time with a little less than 1/2 throttle and less than a minuet the third time. And saw no bubbles like the ones in the radiator ever.

Here is a pic of the thermostat off
29936

Thanks for the help. I am sure the system will settle down eventually.

If there is anything you can think of that I did not do to eliminate a head / head gasket problem please let me know.

What i would do is disconnect the serpentine drive belt,remove the coolant cross-over that connects to both cylinder heads and run the engine that way.If you see no bubbles from either exposed coolant port,i would'nt worry about it.

Looks like i overlooked your last response.Seems as though you've already disconnected the belt.If there are no bubbles,you should be okay.

If you notice in the picture with the thermostat being as it is you can even tell which bank would be blown without removing the crossover.

Looks good to me... :)