Advice on 3-FE Timing, Head Gasket, and Overheating

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Jul 23, 2013
Salt Lake City, UT
Some background, my 92 has 302K, the temperature gauge has never moved above half way. A couple weeks ago I drove home, turned off the truck and a couple hours later it would crank but not start. I traced the issue to the distributor/rotor/cap which were all in poor shape. I decided to replace them all due to leaking oil from the O-Ring.

I followed the FSM procedures and installed a new AISIN heavy duty black fan clutch for good measure, and a bunch of vacuum lines which were in poor shape. Buttoned everything up, and set the timing to 7 degress BTDC. Ran like a dream in down and idled nicely. I opened the rad cap to burp the system (had to remove the rear heater core line to remove the valve cover), and after it burped there were no more bubbles in the the system, even when revving the engine a couple times.

So, last weekend I was on a trip to Flaming Gorge and after we started getting into the longer mountain climbs we started to overheat at higher RPMs. The temp gauge never went above the 3/4 mark, certainly never to the red, and only was there for a couple minutes at most. I am aware this is a relative mark, and with an engine this age, could result in a blown HG at any point above normal.

Here's my rub. I took the cruiser into a local mechanic which does a good deal of Cruiser work and I have used them in the past. I asked them to verify the timing, and confirm the new distributor was advancing properly, as that appears to be the most likely reason for overheating at higher RPMs given what I had been messing with.

They did some testing, said my timing was pretty much the mark, but my head gasket was bad, as judged by the gas analyzer machine. I conceive this is totally possible, and requested a compression test. However, I am not convinced the HG caused the overheating, rather the opposite.

This truck never ever overheated, and if the timing was on, this has to be caused by poor timing caused by a malfunctioning distributor? It seems wild to me that this vehicle did not have HG symptoms before, then after repairing a different issue, the HG is instantly bad enough to cause the overheating that has never happened before.

If anyone can give me advice on what to check or verify. If I have to repair the HG, that is what it is, but I am not convinced this was the cause of the issue in the first place.
Sorry, but I have to ask. Is there any chance that when the clutch was replaced, the fan got flipped over?
Sorry, but I have to ask. Is there any chance that when the clutch was replaced, the fan got flipped over?

Its possible, I had read some related threads where this same question was asked. It is on my list of things to check, but I do not believe it is the cause. The truck seems to bog down approaching 3K rpms and does not have nearly the same power as before. It used to run smoothly up until it shifted, no it seems to peter off the higher the RPMs go. If it was purely temp flux I could easily see this, but I am getting immediate engine abnormalities directly correlated to this.
Have you checked the dynamic timing? Maybe it's not advancing.

This was my original question I wanted answered by the mechanic and did not really receive an answer. This is way more difficult to confirm in a 3-FE since you can only see the timing mark for a very brief period since you have to look through a hole to the flywheel. It might be possible to see if it moves at all, but probably very little beyond that.
It is hard to see but a mirror might help or standing just in the right place. What I do to get an idea of the dynamic timing is try different total advance -7 on the dial of the light and look for the timing mark on the flywheel to match up. It's easier to see than TDC.
You could send a oil sample to blackstone and check for coolant in the oil. As far as overheating goes the cooling system is composed of many parts all of which play a role. As an aside, I'm running my original green hub fan clutch with 10,000 cst silicone and this really pushes allot of air. Also how's the condition of your radiator and water pump?
Also how's the condition of your radiator and water pump

Water pump, thermostat, radiator, upper and lower hoses, Toyota red coolant, fan clutch are all new within the last year or two. Fan shroud and fan blades are in good shape. I don't mess around with the cooling system living in the desert.

Again this truck has never ran anywhere above mid-line, and immediately overheated above 2500 rpms following the dizzy install. I do agree, verifying the advance is probably the biggest priority here, if everything seems to be in working order.
If you want to drive down to Mapleton this weekend, I can help you check the timing.
I can also have an oil sample kit on hand.
If you want to drive down to Mapleton

I just left a message with Expanded Metal Works in Mapleton to see if he would do the gasket replacement. I really just want to know if I have a dud distributor. I can swallow the head gasket, this truck has been loyal and forgiving for 300K miles, it has earned some new gaskets and maybe a rebuilt head. The distributor thing just gets under my skin since it is brand new, and was a pretty big PITA to get everything dialed in.
The dynamic timing issue seems plausible. The head gasket does not due to your experience. 3FE's are not known to have head gasket issues due to the iron head. About 100k ago I had my son's 92 in the red on a steep slow hill climb. Call me lucky, but the head gasket is original with almost 400K on it. For your 92, I would recommend changing out the fan clutch fluid to 15K cst.
I agree with Summit, but I would also STRONGLY suggest a new OEM green hub fan clutch. 3FEs NEVER used black hub clutches so your fan could be sitting in the wrong place in the shroud yielding less airflow.
Black hub and blue hub were used on the 1FZFE motors.
The green hub clutch also has more fluid shearing rings and will generate more airflow in their stock form than either a blue or black clutch.

It is not possible for the fan to be reversed on the clutch as the body of the clutch fits into the cavity in the fan.
Well, I suppose you COULD if you really wanted to, but that would be like mounting your wheels inside out.
STRONGLY suggest a new OEM green hub fan clutch. 3FEs NEVER used black hub clutches so your fan could be sitting in the wrong place

I am not sure when or if the fan clutch I pulled out was last changed, it was a Green clutch. The AISIN fan clutch I installed was the FCT-009 from Cruiser Outfitters, listed as the Heavy Duty replacement for 2F/3FE engines. I was going to replace the clutch oil with a heavier weight but I was trying to move the repair along...which is now in week 3.
If you still have the green hub clutch, I would change the oil in it and run it. Not familiar with the FCT-009. With the 3FE I wouldn't go any thicker than the 15K. I have tried 20K and at 100 degrees it stays locked up most of the time at highway speeds. This is extremely detrimental for the 155hp of the 3FE. As mentioned, the timing and how it advances under higher rpms sounds like the real issue. The fan clutch fluid will help at low speed situations.
One more, make sure the distributor cap has the vents in the top and they are hooked up. If not, your distributor pickups and related parts will accelerate with corrosion.
It wouldn't take long now to replace the fluid in the old clutch and try it. Or try it now and replace the fluid later.
Did you have to turn the distributor near the limit when you timed it or is it nearly center? I'm wondering if it could be off a tooth and there's not enough advance left before the rotor is out of firing position at higher RPM. I'd think that would misfire a lot but .... Also, I do think you have two possibly unrelated issues going on.
I felt pretty good where the dizzy was seated. I had it almost perfectly on center of the channel pointing at cyl 1 on TDC. Timed to 7 deg BDTC, it was not that far from the middle. I assume that as long as it is comfortable timed, the electronic advance is independent once it is tightened into place? I read a bunch of "off by one tooth" threads, but they all seemed to be maxed or unable to get to 7 deg. Something to check out, I have learned a great deal about this system from this ordeal, I have never had a vehicle that didn't have coil packs before this.

The dizzy is properly vented and I replaced the hoses, the previous hoses had fallen apart and that left the insides of the old dizzy in pretty horrible shape. That and the leaking oil was part of the reason I thought it was worth while to just replace it.

I have a hard time believing brand new parts are bad. I know it is perfectly likely given bad quality control but I want to rule out user error/my ignorance before I start pulling off new parts. The fan clutch I think is a separate issue. At this point, my attention is focused on the dizzy.
Yes, if you're near the middle at base timing, it's good. I missed the fact that the entire distributor was new. They still sell them?

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