New to the forum here and thankful such a place exists. I've always done my own vehicle repair work and have always been able to figure out a fix for just about every vehicle I've owned but this issue has got me stumped. I picked up a used 98 (4X4)Jimmy with 120k on it with an engine problem for a good price. Which, is a loud metallic ticking sound. If you check this video out, http://www.youtube.com/watch?v=ikmJ4-RcGDw&feature=related (its not my video but it is exactly the same sound we have) you'll hear the issue we have.
First off there was the check engine light on and a non working tach. I dont know what the codes were because the truck needed a new battery and we (my son and I) picked up a new one and on the same day pulled the valve cover off of the suspected side of the engine and removed all the rockers and push rods. We cleaned them and inspected for wear. Not finding anything noticeable we reinstalled them where they came from originally and torqued the rocker arm nuts to specs and replaced the valve covers. No change -
Then we tried some Marvel Mystery oil combo with an oil change in hopes it might be a stuck or frozen lifter. No change.
Next repair attempt was to research and read up on the stock intake manifold gaskets being prone to anti-freeze leakage into the lifter/cam/ balancing shaft gallery. Upon opening it all up, we found out that the prior owner had done the same repair with Fel-Pro gaskets. I thought perhaps he didnt clean the mating parts well enough as I found small amounts of coolant at the rear of the of the engine. Shop vac'd it out, wiped down and cleaned out best I could. Then, opened the drain plug to the oil pan and poured fresh oil over the lifters basically to flush. Leaving it to drain for an hour and refilled it with oil. Reassembled and started - no change in noise. But now no check engine light, no codes and got the Tach back to working again. Since we were letting it run now in hopes the noise would depart I noticed a fair amount of water vapor coming from the exhaust and lots of water droplets leaking down from the tailpipe. The vehicle had plenty of heat when you turn it on but the coolant reservoir did need some topping off when we first got it.
Then we tried adding a half of a pint of Sea Foam.. persisting on the stuck lifter theory. No Change.
I read up on timing chain issues for the 4.3L and saw the article about the worn timing chain tensioner issue. In running the engine and revving it up as it slowed down I heard the cackling sound of a loose timing chain and though with some play in the chain perhaps there was play in the cam gear and balancing shaft gear. Upon opening er up again we did find the timing chain indeed sloppy and replaced it (no tensioner in this engine). Put it all back together, started her up. Runs smooth as a kitten, plenty of power. Tapping not gone and still droplets of water from the tailpipe and water vapor. No clouds mind you. Not sure if this is normal in a 4.3L.
So now we are looking at replacing all the rocker arms and push rods on the driver's side. We did roll the existing ones on a piece of glass for straightness. All twelve are fine. Also we got a piece of heater hose and checked various places around the engine to isolate the noise. The most noise centers around the middle cylinder on the drivers side.
Any one else have this problem and fix it without throwing in a junkyard, rebuilt or new motor? Thank in advance for reading and recommending possible solutions (if any besides a new motor).
First off there was the check engine light on and a non working tach. I dont know what the codes were because the truck needed a new battery and we (my son and I) picked up a new one and on the same day pulled the valve cover off of the suspected side of the engine and removed all the rockers and push rods. We cleaned them and inspected for wear. Not finding anything noticeable we reinstalled them where they came from originally and torqued the rocker arm nuts to specs and replaced the valve covers. No change -
Then we tried some Marvel Mystery oil combo with an oil change in hopes it might be a stuck or frozen lifter. No change.
Next repair attempt was to research and read up on the stock intake manifold gaskets being prone to anti-freeze leakage into the lifter/cam/ balancing shaft gallery. Upon opening it all up, we found out that the prior owner had done the same repair with Fel-Pro gaskets. I thought perhaps he didnt clean the mating parts well enough as I found small amounts of coolant at the rear of the of the engine. Shop vac'd it out, wiped down and cleaned out best I could. Then, opened the drain plug to the oil pan and poured fresh oil over the lifters basically to flush. Leaving it to drain for an hour and refilled it with oil. Reassembled and started - no change in noise. But now no check engine light, no codes and got the Tach back to working again. Since we were letting it run now in hopes the noise would depart I noticed a fair amount of water vapor coming from the exhaust and lots of water droplets leaking down from the tailpipe. The vehicle had plenty of heat when you turn it on but the coolant reservoir did need some topping off when we first got it.
Then we tried adding a half of a pint of Sea Foam.. persisting on the stuck lifter theory. No Change.
I read up on timing chain issues for the 4.3L and saw the article about the worn timing chain tensioner issue. In running the engine and revving it up as it slowed down I heard the cackling sound of a loose timing chain and though with some play in the chain perhaps there was play in the cam gear and balancing shaft gear. Upon opening er up again we did find the timing chain indeed sloppy and replaced it (no tensioner in this engine). Put it all back together, started her up. Runs smooth as a kitten, plenty of power. Tapping not gone and still droplets of water from the tailpipe and water vapor. No clouds mind you. Not sure if this is normal in a 4.3L.
So now we are looking at replacing all the rocker arms and push rods on the driver's side. We did roll the existing ones on a piece of glass for straightness. All twelve are fine. Also we got a piece of heater hose and checked various places around the engine to isolate the noise. The most noise centers around the middle cylinder on the drivers side.
Any one else have this problem and fix it without throwing in a junkyard, rebuilt or new motor? Thank in advance for reading and recommending possible solutions (if any besides a new motor).