HELP! Running/Power/Timing issues

[eshom77]

Well, I finally got my truck back. It took a total of 22 days, more than I wanted to spend, and countless hours lost in income and productivity, but it is finally out of the hands of the bumbling, idiotic mechanics at the garage in Fraser. The altitude is tough on this truck, as WP being at 9000 ft, and the top of Berthoud pass being at 12,000 ft the vacuum problems I'm having truly wreak havoc with the power of the truck. We had to advance it wto 23* just to get it to idle and even then starting it was a feat. I'll admit my ignorance, but after I've checked spark, fuel, timing and the basics, I'm still learning the finer points of diagnosis and troubleshooting. i'm not a mechanic, and although i understand how cars work pretty well, i don't have a ton of practical experience beyond maintenance and some of the more basic proedures. What frightens me is thath I definitely knew more than mechanic who has been holding my truck hostage for the last 3 weeks. I don't know much, but I'm learning.

After a long trek over the pass, (at about 12mph, in Low) I've finally made it back to Denver. I planned my route strategically to incorporate the fewest uphill grades possible. Monday I have an appointment with a mechanic I know and trust here in Denver. With his help in diagnosis, I can hopefully take care of much of this myself.

After replacing entirely too many parts, I've finally narrowed it down, and I'm fully expecting to find a serious vacuum leak upon inspection. Here's the lock: climbing a hill, when the carb fan turns on I have a drastic reduction in what is already feeble power. That seems a pretty clear indication of a severe vac leak to me. The carb also needs some good lovin'. when the engine is revved, you can hear air being sucked near the carb very loudly. Am I off base on this?


The saga of the Cruiser continues. Sunk too much $$ into it to sell it now...

--'86 Fj60 no desmog, emissions re-wired since I bought it. It's registered in a no-emissions county, should I just disconnet everything & bybass the cat?

FFJ40Jim, how common is elastomer failure on the cam gear?

 

[FJ40Jim]

Cam gear fgailure is not common on the toyota gear. I've only seen 3. It is more common on the Chevy version, but then again there are more of those engines around. But again, it matches your symptoms exactly.

This is not symptomatic of severe vac leak or stuck EGR. Severe vac leak would be most obvious at idle (no idle or very rough idle, symptom goes away at high throttle settings).

With no power at any RPM, and having to advance the heck out of the ignition timing, this indicates that all the power/compression is blowing out through the open valves.

 

[eshom77]

Alright, so it sounds like the cam timing truly is the most likely issue. I'm bringing the truck in tomorrow morning. What are the smoking guns on this condition? Low compression, the complete lack of power? The low rpm power has always been especially bad--lots of clutch slipping just to get the truck moving without stalling out under it's own weight. Having to stop on even a reasonable uphill slope, say coming out of a driiveway that's below street level, has pretty much always meant putting it into Low just to get it moving...

How about losing power when the carb fan turns on and regaining it when it turns off?

Would the cam gear failure be pretty obvious upon direct inspection after removing the cam gear cover? What should I look for? Will there be play in it as it sits on the camshaft or what? I just want to go in armed with as many likely possibilities tomorrow...

My mechanic down here hasn't come across the cam gear failure firsthand himself before, so he's reluctant to accept that this might be the problem--doesn't think it is that likely, but if it's not a common thing then I can see why.

I'll have to verify this tomorrow, but I think its holding timing now... Is all this cam gear stuff out the window if it seems to be holding the ignition timing?

Any additional advice here is appreciated. Thanks for the guidance everyone has offered so far.

 

[FJ40Jim]

Alright, so it sounds like the cam timing truly is the most likely issue. I'm bringing the truck in tomorrow morning. What are the smoking guns on this condition? Low compression, the complete lack of power? The low rpm power has always been especially bad--lots of clutch slipping just to get the truck moving without stalling out under it's own weight. Having to stop on even a reasonable uphill slope, say coming out of a driiveway that's below street level, has pretty much always meant putting it into Low just to get it moving...

Yes, those are the smoking guns, along w/ ignition timing that keeps getting retarded.

How about losing power when the carb fan turns on and regaining it when it turns off?

That is a separate electrical issue. The carb fan is not able to turn on w/ the engine running. If it is coming on, then there is an electrical gremlin that needs dealt with.

Would the cam gear failure be pretty obvious upon direct inspection after removing the cam gear cover?

No. not visually obvious.

What should I look for?

Degree the cam. If the dots are lined up correctly, but cam timing is off, then cam gear is failed.

I'll have to verify this tomorrow, but I think its holding timing now... Is all this cam gear stuff out the window if it seems to be holding the ignition timing?

That's a personal decision, whether to fix or ignore the problem.

 

[eshom77]

Thanks, Jim. Got it into a reputable mechanic this morning who has worked on my vehicle before. Doing a full diagnostic--compression, vacuum, electrical, etc. I should have some answers to my many questions here shortly. We'll see what happens now. Judging from the number of Landcruisers I always see in this shop's lot, I think I'm in good shape.

The value of a trustworthy, competent mechanic is truly priceless.

 

[eshom77]

FJ40Jim, you were right on with the cam gear diagnosis. Compression tests yielded about around 75 psi in all cylinders, with one down in the 60's. It's a wonder the truck even runs at all. So, while it is good to finally have the problem cornered here, I'm now faced with the dilemma of how to pay for it.

My mechanic said he has come across it once or twice, but never to this degree. Depending on how much trouble he has getting the gear off the camshaft, I could be looking at a pretty heavy labor bill. At least parts aren't too expensive.

It's got to be done, that's for sure. This is the problem the truck has had from day one, and why I've NEVER made power, no matter how much work I sunk into other areas of the truck.

Anyhow, got a lot to think about. Thanks for the guidance.

This truck is going to want my first born.

 

[FJ40Jim]

Dayumm, I'm good.

Glad you got it figgered out.

 

[Mace]

Should not take more than 10 mins to cut the gear off of the cam..

Maybe a PITA but not labor intensive..

 

[FJ40Jim]

Cut the gear off?
Shouldn't it just press off?

And a new one gets pressed on?

 

[Mace]

Yep, but sometomes a cutting wheel is Faster...


Besides, don't you want a pic of a gear cut in half???

 

[eshom77]

back in business

Hey all. Well, its been more than a month since my last post, and the Cruiser is finally back in commission. The camshaft timing gear was indeed the problem, and judging from how my truck is now running, has been the problem since the day I bought the truck from the PO. It feels as if the truck makes about twice as much power as I've ever felt it make, so I'm pretty happy. After a year of the beast either barely running or not at all, I remain a bit gunshy, but I'm hoping after all these problems that the major problems are behind me. Pretty sweet having a vehicle to drive again after not having transportation for more than a year. Thanks for everyone's help and insight on this board, you all were a huge help in getting the problem diagnosed and dialed in.