Help- coolent problems/ water pump

[rturbett]

Guys, I could use some help with diagnosing this.

Did the head gaskets 6 weeks ago, 1990 RRC has been running great ever since. (Thanks for all the help) I flushed the radiator at that time.
Today, 90 miles into a trip, the truck overheated. Was losing radiator fluid from the resivoir. (over full, pressurized and hot)
I dont see how it could be the head gasket-but that would be my guess.
What problems would a bad water pump exhibit? there was a teaspoon of fluid next to the pump, but nothing excessive. (could have been overspray)
Going in to change the pump and thermostat now. Please let me know if you have any advice.
Thanks,
Rob Turbett

[OkieRover]

You did the head gaskets? And you are getting pressurization?
DO a hydrocarbon test on the coolant that will be the quickest way to tell if you have head gasket trouble.
After my head gasket issues I just completely replaced my radiator. I had it rodded twice and it still clogged.

[rturbett]

I'm hoping its the water pump- working on getting the viscuous coupling /fan assembly off now. I will flush the radiator again- it was clear when I did the heads.
I boiled the thermostat, and it worked fine. I will replace it anyways

[57loboy]

Make sure it goes in the correct way - if reversed, they won't work...

[TerryS]

As Okie said, Do a hydrocarbon test before you waste any money swapping out parts. You can get it done in about 2 minutes at any service station that has an emmissions scope or you can buy a test kit from NAPA, Carquest, etc. The service station can take their wand, place it over the expansion tank cap, or 3/4" radiator plug and detect if there are high hydrocarbons present. The kit from the autp parts store consists of a clear vial which, with the test fluid within, is placed on either the radiator cap or expansion tank opening. A vacuum bulb on top of the vial pulls air through the liquid. If hydrocarbons are present, the test liquid will change from blue to yellow.
Hydro carbon exhaust gasses present in the cooling system tell you that there is a leak between the combustion chamber, into the cooling system, pressureizing your cooling system, lifting the expansion tank cap (if not blowing it entirely) loosing fluid, and THEN overheating. The frequent, and incorrect assumption is that the coolant loss is the result of overheating, when the reverse is almost always the case.
OK, so now, where the gasses are leaking through is the next issue. It's possible you didn't install the new head gaskets correctly, or the heads were warped such that they didn't seat correctly, but the more likely issue is there is at least one, and frequently two adjacent liners whose bond between themselves and the block has loosened. If you recall, when you put the new head gaskets on, the hole in the gasket is slightly larger than the actual bore. That means, when the heads are socked down tight, there is a gap there that could allow the liner to lift, up towards the head by about .025 - .030". If the leak path is great enough, coolant can seep into the cylinder when you shut down and the engine cools. Evidence of this is a very clean spark plug, since it's getting steam cleaned. The leak path isn't usually that great, and the cooling system is getting pressurize by the combustion chamber pressures when the cylinder is firing. lots of people will tell you to do a compression check, and while this may indicate a blown head gasket, you're only going up into the 120-150 psi range as opposed to the 4000-6000 psi range from combustion of the compressed gasses.
The symptoms rarely manifest themselves driving lightly around town, but almost always on the highway, at extended engine revs. I've heard of people living with it for long periods of time because they just drove around town, and left their expansion tank cap loose.
Before you do anything, fill your cooling system and take it up the highway and back 20-25 miles, then check inside your radiator. Bet you're down at least a quart, 3-4"
There is no economic fix for the "dropped liner" (another falacy, as the liner doesn't 'drop' it goes up at first, then up and down alot till it hammers the shelf in the bock so it then goes down bleow the deck level) syndrome, short of going out and finding a good used engine, or block at least.
BTW, you know the viscous fan clutch is Left hand threads.

[rturbett]

Thanks for the info- I did confirm with AB that the threads for the viscous coupling were reverse- before I cranked on it. So I did get the waterpump off today and as you may have guessed, it looked fine.

I do have some "leftover" radiator fluid that I have not contaminated that I can test.

This was my first head gasket job, so I can accept that I did a less than perfect job. I did have the heads machined, and I was meticulous with the torque sequence.

If I do take the heads off, what do I look for to confirm the dropped liner theory? I'm not familiar with this.
Thank You,
Rob Turbett

[TerryS]

Originally Posted by rturbett

So I did get the waterpump off today and as you may have guessed, it looked fine.

Water pumps rarely go bad in these engines, So, I'm not at all surprised.
Before you even take the heads off, do the hydrocarbon test. You won't be able to do it afterwards, since the engine needs to be running. Testing any fluid, not in the car is wasting your time, as HC will have dissipated.
If the test comes back positive, and I suspect it will, don't even bother pulling the heads till you've determined you can't find a long block. If all you can find is a shortblock and you need your heads, when you pull them, look for a "ring" imprint, with the ID and OD of the liner, on the head, around the combustion chamber. Also, look at the joint between liner and block.Sometimes there will be little or no indication that the liner has 'moved' at all, but if it has, you'll be able to hook your fingernail on the OD of the liner. A bad liner may well be protruding the deck surface.
Stick the pump back on, start it up and do the hyrdocarbon check before you expend any more energy. You'll need to let the engine warm up. When you rev the engine, look inside the rad plug for loads of tiny bubble when you rev it. If thy are there, well, I guess you know the rest.

[rturbett]

If I have eliminated the thermostat, waterpump, and no blocks in the radiator and heater core, than it could only be a gasket issue or cracked head/block- Correct?

The engine has 75,000 on it. Pretty low by comparison to a lot of the used engines for sale. My thought is I probably messed up the head job- It would be a bit of work to do the hydrocarbon test at this point. ( i should have done that before anything else. Good lesson learned...)

I will probably take it all apart this weekend, and look for anything obvious, and have the machine shop look at the heads again.
This will give me the chance to fix the lifter that I missed first time around.
Now that the engine is clean, it will be much easier to work on. Lots of new bolts too, so that will help with removal. Plus I know how to do it now.
Assuming I don't find any ridges around the combustion chamber,do you have any pearls of wisdom for seating the gaskets?
Thanks,
Rob

[TerryS]

Originally Posted by rturbett

If I have eliminated the thermostat, waterpump, and no blocks in the radiator and heater core, than it could only be a gasket issue or cracked head/block- Correct?

No. I have seen cracked heads. The crack usually appears inside the exhaust valve pocket. I haven't seen a cracked block but I've heard some say they have. The leak between liner and block is the most common of the incurable overheating problems

Originally Posted by rturbett

The engine has 75,000 on it. Pretty low by comparison to a lot of the used engines for sale.

This problem can occur on the older engine design at any age. It is almost always the result of a severe overheat event, from a burst hose or no coolant. It then becomes a continual overheat problem when the coolant is blown out due to pressurizing the cooling system. I replaced a 60k engine in my NAS 110 with an engine that had over 100K, but I completly built the engine to new before puting it in.

Originally Posted by rturbett

My thought is I probably messed up the head job- It would be a bit of work to do the hydrocarbon test at this point.

I doubt you messed up installing the new head gaskets. I'm assuming you used the new style, composite head gasket with stretch type head bolts. These bolts aren't so much torqued, as tightened until the bolt reaches it's yield strength. (tighten to 15 ft pounds, then 1/4 turn, in sequence, then another 1/4 turn in sequence)

Originally Posted by rturbett

I will probably take it all apart this weekend, and look for anything obvious, and have the machine shop look at the heads again.

Did the machine shop either crack check them with dye penetrant or pressure test them?

Originally Posted by rturbett

Lots of new bolts too, so that will help with removal. Plus I know how to do it now.?

Technically you can't re-use stretch head bolts, because they have already been stretched to their yield strength.

You can do whatever you think is easiest, but if you'll take some advice, it is far less work to out the water pump back on, and test it deffinatively for hydrocarbon leak (= liner issue), which seems to me to be alot less work.
Or, take it all apart, look for something that may very well be there that you can not see, put it all back together again, and still have the problem.
Sometimes, doing it the hard way teaches a valuable lesson. Trust me, I've learned the hard way on a few, but I've built or rebuilt countless of all types of Land rover engines since my first one in 1970.

[rturbett]

I'm guessing a cracked head. hoping to find it so that I can rebuild it without doing the block.


I did use stretch bolts. Someone else on this forum taught me how to use them correctly. Perhaps they were tighter than the 15lbs before I started the 1/4 turn (x2) process. That could be a source of uneven stress on the head.

The shop pressure tested them, but I only recall talking about the valves all seating fine. They have been great, and helpful in teaching me along the way.
(They really enjoyed hearing my son and I were doing this for fun)


I used a lot of new bolts along the way, but I would never re-use head bolts.

I truly appreciate you guidance. The way I see it, If I put it back together and get a positive hydrocarbon result, I still don't know where it's from.
If I do take it apart, i'm out about $130 to put it back together- two head gaskets and new head bolts. (I have another vally gasket)
Bonus is taking care of the bad lifter!

Worst case is not finding any problem, rebuilding it, and still having the problem....but a hydrocarbon test will tell me whats up...

[rturbett]

Terry, your going to love this!
Took the heads off. All bolts were consistently tight. Some of the bolts on the drivers side had an oily sludge around 4 or 5 threads in the midsections. There was a lot of gritty oil on the top of the combustion chamber and around the gaskets- on both banks. This area was close to pristine just 1000 miles ago. The spark plugs were fine- one with just a hint of fouling.
No obvious marks around the gaskets- the engine shop will inspect them for me as well- for diagnosis, not re-use.
There was never any smoke out of the exhaust.

The engine shop is looking at the heads to confirm all is well-
There initial guess is that the rings are bad, letting oil build up and raise the compression
to the point the some part of the gasket fail.

PS- all sleeves seemed fine- there is a slight chamfer at the top of each chamber, but no step indicating a dropped sleeve.

Let me know what you think. It burned one and a half quarts of oil in the 1000 miles we put on it.

[TerryS]

Are you sure you didn't install the head gaskets wrong way around so that the oil passageway from block to head was blocked? Going from memory, the oil hole in the block deck is between the cylinders 1 & 3 on the left side, and between 2&4 on the right side.

[rturbett]

Positive the gaskets we aligned correctly- we put 1000 miles on it since we did the heads first time around.

Any issues with different head gaskets? We used the ones that come in atlantic british head kit.

The shop says the heads still look fine, but they are giving them a thourough inspection.

Rob

[TerryS]

If the rings were bad enough to loose 1.5 quts in 1K miles, you'd be seeing blue smoke. What's the inside of the tailpipe look like?

[rturbett]

tailpipe was sooty, but not horrendous.

Just took the oilpan off- some sludge, but the pickup screen was clear. Might try doing the pistons with the block still in place.
This is pretty fun! its such a treat to have so much headroom underneath a vehicle!