Well, the good news is, I finally got off my ass and installed the Thorley header I had sitting in my basement the last couple years. The bad news is that when I start the Jeep, the engine immediately starts to rev to redline, even though I don't have my foot on the gas. Anyone know what the hell is going on here? I've checked the throttle cable and that's all well and good. No vacuum leaks that I can tell.
Dave
Doublecheked every connector that you might have taken off to make sure you put it back. The idle stepper motor could do this if its open.
Ya, went down that road already.... at least I think everything is hooked back up. I'll double check though, thanks!
Dave
That sure sounds like a vacuum leak.
Jerry
Thanks, Jerry.... the more I've been sitting here thinking about it, I think you're right. We got lazy and just torqued everything down using air tools, and I have my doubts on how powerful my neighbors compressor is. Think I'll go back and torque to specs.
Dave
Air tools????!!!!!!
Man oh man....
There 'is' a reason they invented torque wrenches....
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's"David C. Moller" wrote:
Ya, checked the spring and the plate... all looks good. And yes, it's the 6, and both intake and exhaust are on the same side. This is looking more and more like a vacuum leak the more I read and talk to people. We must not have gotten a good seal with the gasket. Gonna give it another try tomorrow.
Dave
Red RTV (high temp) Silicone. A very thin coat gives me the x-tra confidence on the intake installs. This is not the lead like gasket that is between the manifold and the head. Just the other seals, etc. I work on boilers sometimes at my hotel/condo and when the emission analyzer shows some goofy readings (burning lean) I need to check and seal these leaks. Red RTV high temp silicone to me is the ticket.
110 except for #11 that gets 100. But that's not all in one throw either.
Woah now, what the heck are you guys bolting onto what?
My book says for a 4.0, the #1 exhaust manifold bolt gets 30 ft lb, the rest 23 ft lb.
Now that is for a Cherokee, but....
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's
No, your correct. I farked up and parsed header bolts as head bolts. See other post.
Re-checked since it didn't seem enough bolts ; section 9-128 gives a better description:
Fastener Numbers 1 through 5-Tighten to 33 N·m (24 ft. lbs.) torque. Fastener Numbers 6 and 7-Tighten to 31 N·m (23 ft. lbs.) torque. Fastener Numbers 8 through 11-Tighten to 33 N·m (24 ft. lbs.) torque.
OK, found the problem.... intake manifold wasn't seated properly over the cylinder head dowel. *BIG* vacuum leak hehehehe. Loosened everything, got everything properly aligned, and torqued to 25 ft lbs. Idled at 2K, so obviously still a leak. Torqued to 30. Now I'm idling at 1000-1200. This still feels a bit high to me though, so may have to tighten some more. Anyone know what the proper idle speed is for a '99 TJ 4.0 5sp is? I can't seem to find it in the FSM.
Dave
Dave Milne, Scotland '99 TJ 4.0 Sahara
Hmmmmm food for thought..... thanks, Bill. We took a look at it when we had everything loosened back up, looking for the problem, and the gasket still looked great. But I'll keep that in mind for sure. Thanks again.
Dave
Spray a bit of TB cleaner on and around the gasket with the engine running. If the rpm changes you have a leak.
oil pressure is quoted as "idle (800)"
Dave Milne, Scotland '99 TJ 4.0 Sahara
OK, will give that a try. Thanks for the tip, Doug.
Dave
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