TwistedWrench

Definitely check that timing, it doesn't have to be quite high enough to cause pinging but can still cause it to run hot. When you're accelerating or under load(which at highway speeds is almost all the time if you don't have the right gears for your tire size) the timing advances. If your base timing is a bit too high, it'll feel like its running great, nice and punchy. But when it advances, you may be reaching the point where it'll start to run hotter. The I6 is a phenomenal engine, but isn't very forgiving of tuning problems.

Again, may not be the problem, but I'll keep my fingers crossed. Timing adjustment sure beats the heck out of a head swap!

Firestorm500

IIRC, retarded timing is what causes an engine to run hot and experience lack of power.

TwistedWrench

Lack of power, yes. Typically advancing the timing too far causes it to run hot. Retarding the timing can cause it to run slightly cooler, but of course take that to an extreme and you cause the engine to work harder, lending to overheating.


If you're within margin(eg 8-12deg) general rule of thumb;

Retard: less power/cooler temps
Advance: more power/higher temps

Again, going way too far either way is a bad thing. Starting will tell you if you've gone way too far. Too much advance and it cranks like your battery is dying. Too retarded and it cranks like mad, but struggles to fire off. Backfire through intake, too much advance. Backfire out exhaust, too retarded.

BlueRidgeMark

I fried a 62 Falcon 6 cylinder due to retarded timing. The rotor had cracked near the metal tip and allowed it to move backwards. I'd guess it was something like 10-15 degrees. Heated up very nicely. No gauge, so I didn't know it until it was too late.

vank

Thanks all. Dug the timing light out after work and what do you know the bulb was out. I'm going to swing by harbor freight tomorrow and pick up a new one but probably won't be able to work on it again until Wednesday. I'll post an update then.

TwistedWrench

The little early Ford 6 should be at 8-10deg, so ya, lol, getting knocked to about 12deg ATDC... I'm kinda surprised it ran long enough to get hot!

We had a little Mustang with a siezed 200 come in, oil pump locked up, sheared the drive gear off the dissy shaft. So everything was pointing every which way but right, lol. Chicken or the egg?

Bustedback

The distributor won't move to adjust the timing.

Firestorm500

He thinks it's possible he got it a tooth off when he reinstalled it.

#1 on the cap should be at 5 o'clock, just for a quick visual check.

If it's where it's supposed to be, we all know what's next.

vank

I checked the timing and it looks like I'm between 14 and 15 degrees (advanced). Moving a tooth on the distributor (or even on the timing chain) I feel would be too great an adjustment when I only need to move 2-6 degrees. Is there any other way to adjust timing on these 4.0s? What would cause advanced timing. Plug 1 is at 5 o'clock as firestorm said it should be.

vank

So I did a bit of googling (shocker I know) and see the dizzy isn't adjustable like those of old, and all indications point to it being installed properly. Looks like some people slot the mount for the CPS (jeep speed guys), but other than that the timing isn't really adjustable top side. I wonder if it's possible my chain is a tooth off? I know the PO had a new timing set installed, no idea why, I just have a receipt for it. Thinking out loud....

BlueRidgeMark

I doubt it would have started that way, but once it was running, it limped along okay. For a bit....

TwistedWrench

Well, that(the chain) would be valve timing, not ignition timing. That 14-15deg is probably about right, with the old style you'd disable the advance before checking the timing. All that can be done on the 4.0 is ensure the dissy is clocked correctly, which it sounds like it is. So very likely not a timing issue, was worth a shot though! Back to square one I guess...

Firestorm500

Head replacement is next.

vank

So the next question is salvage yard or remanufactured head? Salvage yard only wants $75 with core, but then I'd probably want to test it and machined it. Cheapest eBay reman is 350 plus shipping.

Firestorm500

Based on my previous experience with used/remanufactured heads, which I have already posted about, I personally would only buy a brand new, complete aftermarket head.

It's just too much work, time, and frustration messing around with anything else.