Truck running rough and not driveable - help
- Thread starter subzali
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Well this is mysterious...Subzali, did you put those spark plugs in or did they
come with the Cruiser when you bought it? If the latter, perhaps the
PO put in damaged plugs (or damaged them when installing them),
but they limped along until the combination of damaged plugs and
bad gasoline killed the engine.
If you can't see anything in the cylinders, it might be worth putting
in new plugs and a new fuel filter and seeing if it runs.
-Phrog
come with the Cruiser when you bought it? If the latter, perhaps the
PO put in damaged plugs (or damaged them when installing them),
but they limped along until the combination of damaged plugs and
bad gasoline killed the engine.
If you can't see anything in the cylinders, it might be worth putting
in new plugs and a new fuel filter and seeing if it runs.
-Phrog
- Thread starter
- #23
I put them in while doing a "new vehicle" tuneup just after I bought almost exactly two years ago. I've taken it off-road many times since then and on some small road trips, so I've probably put about 10,000 or 15,000 miles or so on it since I've owned it. I *think* I had a leaking brake booster (which could have been going on for who knows how long), but I thought I got that taken care of this past summer. Maybe it was too late, a guy from Rising Sun suggested that the lean condition of cylinders #5 and #6 can cause them to run hot and disentegrate. We also thought about carbon buildup, but I used some of that de-carbonizing stuff last spring, and it didn't smoke very much, so 
. Anyway, I'm going to take a close look at it once I get it to my parent's house, and keep everyone updated.
. Anyway, I'm going to take a close look at it once I get it to my parent's house, and keep everyone updated.
I think grant5127 is correct on this one. That would explain all the carnage.
subzali, looks like your engine ingested multiple foreign objects. I wouldn't crank it over with the starter motor or you risk further damage to pistons, head, ect...
I would loosen all of the rocker arms so the valve adjustment screws are not contacting the valves. At this point all of the valves should be closed, meaning each cylinder should hold any air injected into each cylinder. A cylinder leakdown tester will allow you to "charge" each cylinder with compressed air and check for sealing. If you charge each cyl. one by one, and you find leakage, you can check to see if leakage is passing through the exhaust or coming through the intake (at the carb). This will determine which valves are bent. With plug damage like that, I suspect you have valve damage.
I would loosen all of the rocker arms so the valve adjustment screws are not contacting the valves. At this point all of the valves should be closed, meaning each cylinder should hold any air injected into each cylinder. A cylinder leakdown tester will allow you to "charge" each cylinder with compressed air and check for sealing. If you charge each cyl. one by one, and you find leakage, you can check to see if leakage is passing through the exhaust or coming through the intake (at the carb). This will determine which valves are bent. With plug damage like that, I suspect you have valve damage.
- Thread starter
- #26
grant5127 said:
I'll have to look into that...but maybe someone can give me a quick edumication on how this happens/how this is possible?
At this point I'm just going to park it and disassemble it. It's not a daily driver (once I get my red truck back), and if anything major IS wrong it'll have to come apart anyway, besides it will be an education.
One question though: With the engine still in the truck, how hard is it to pull the head? I've heard that sucker is pretty heavy...would it be worthwhile to pull the hood and the fenders/bib?
And I'm scared that running it to get it home and turning it over to check out the valves might have made the damage worse...
and this engine's already been bored 0.030 over.
BTW, how much overbore can these engines take?
the cam gear has a rubber damper incorporated into it that normally with age will fail.... a simple check would be to rotate #1 cyl @ tdc a do a visual of the valve train arrangement and make a note, repeat 2 or 3 times more each time observe the results... but before a total dissemble do a leak-down test to get a idea on the total overall condition of the motor..and go from there...
How the engine was maintained over the years has alot to do with it... high levels of HCs will cause the damper to decompose faster than normal.... I can post a pic tomorrow of a spun-out if ya want... have a couple @ my shop.....
I have seen a few engines that had broken timing belts or chains and this will sometimes cause a couple of bent valves and maybe cracked pistons, but they don't generally mangle the spark plugs. I'm not even sure that valve piston contact is possible in an open chamber 2F.
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X2.
Also, piston to plug contact looks pretty impossible.
Your engine has timing gears, not a chain. Here is a pic of one Coolerman posted in the best 2F thread. Who knows what condition yours is in but you never know. Call me tomorrow if you need me to trailer the truck to the shop.
one example...... https://forum.ih8mud.com/showthread.php?t=108749&highlight=cam+gear solid gear, but you can get the idea... the solid gear tends to produce a noise that's not desired by some folks... reason for the rubber....
anyway.. jumped valve timing doesn't have anything to do with piston / plug contact... that's why I suggested a further evaluation...
anyway.. jumped valve timing doesn't have anything to do with piston / plug contact... that's why I suggested a further evaluation...
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as you can see in the pic.. the closest object to the plug is the intake valve.... when the valve train jumps time the piston strikes the valve causing it to bend, in some cases far enough to damage the plug....
The fact it's running at all seems to me to rule out a timing gear. Pulling plug wires & getting little or no RPM drop on 4 cylinders out of 6? All I can say is tractor engine. The only times I have seen plugs whacked like that was when plugs with the wrong heat range were installed & the pistons hit them, not likely, I think with the closed-chamber design but what about the open with the domed pistons? Are they close enough to hit a too long spark plug?
- Thread starter
- #36
Yeah, tractor engine is right. It was for sure running on 3, but quite possibly two cylinders. I couldn't believe it. Anyway, how's 0.675 look for the distance from the washer to the end of the threads on the plug? They are NGK GR4 plugs.
A hotter plug has an extended ceramic core but the threads are the same length. It takes longer to transfer heat to the head than a shorter core, so stays hot longer. If you have ND W14EX or NGK BP5EZ, or equivalent, the recommended plugs per my 1988 2F FSM, they are probably not your problem. I'd start with the leak down or a compression test as recommended above.
- Thread starter
- #38
Got the head off tonight with my dad, I forgot my cable to connect my camera to my computer, but I'll post pictures Sunday. Imagine those hose clamps that have the springy wire and the bolt with the 10mm hex/philips head that compress it, and imagine that the bolt is stuck into cylinder number 5's intake and keeping the valve open while the spring is stuck into cylinder number 6's intake and keeping the valve open. The cylinders appear to be okay, but the piston faces are pretty banged up. Valves appear to be okay, but who knows about the seating surfaces. We were able to compress the springs and get the pieces out, but I have no clue how that got in there. I had the carb/intake out during the summer a year and a half ago, but we cleaned out the intake and made sure it was clear. I *might* have had the carb off since then, but definitely don't remember anything falling in there, and I know I was pretty careful. I don't think there is any way this thing could have fit down the throat of the carb. Also, since I last had the carb off I've done Chinaman's, Triple Bypass, driven to Buena Vista/Leadville, did the Ghost Town Run, driven to Westcliffe/up the road to the Crestone Peak and Needle, and driven to work a LOT this summer, not to mention a bunch of other smaller trips here and there. I guess I coudn't be happier about the location of where it decided to let go, but still it's weird.
So the question is: what would YOU do?
So the question is: what would YOU do?
ok, so how did the one spring clamp get into three cylinders?