jfz80
Cruisin’
Ok ill try to include all the pertinent info here and hopefully my curse of horribly titled threads wont continue. Im really just looking for opinions of those that are more familiar w/ these beasts and might have had a similar problem; or suggestions of next stage of diagnosis.
Vehicle: 72 FJ55, SOA w/ a BL as well, 1 F motor, 4spd w/ a three speed t-case, front disc axle, saginaw steering, WELDED REAR, and some sweet chatanooga cruiser custom van seats.
HIstory: Ive had the cruiser for a year now and have redone the PS system as well as the clutch now, and then just small issues beyond that.
Issue: Last fall i had intended to tow the pig to the Pumpkin Pig Run in the NC mtns. Well when the towrig plans fell through i dove in the day of departure and changed all fluids (motor,diff, tcase,tranny, and brake as well) checked the nuts and bolts, crossed my fingers and headed out. 7hrs later i was there, but the issues had begun. On the climb to the cont. divide on I-40 i started to get a knocking noise only in the higher end of rpm band. I stopped and rested but being 5.5hrs in i continued on. I got a couple days of trail in before it appeared the clutch was not holding for the hills, so i got out while i could and had the pig towed home.
sorry, so the issue is a pretty loud knocking noise as i get up to speed more than up to rpm. the symptoms occur in first while accelerating, second not so much, third ABOVE 40 ONLY, and fourth gear ABOVE 50mph only. You can put as much load as possible on drivetrain, but it will only occur once up to these speeds? once at 50mph in 4th you can let off and it goes away and when barely feathering the gas (if still at speed) it comes right back, no hesitation, w/ very little load on the system. It does not happen while revving engine in neutral. I can feel a knocking in the t-case by touch while driving. Starting to believe it might be a t-case issue but it will still Knock in nuetral, with the clutch in??
What ive done: I inspected clutch for a bolt backing out of the pressure plate, no luck, but i went ahead and replaced the whole clutch assembly. I dropped each drive shaft and inspected U-joints (they feel good to me, but ive never felt a bad one) but they do not have excessive play. The key fact that stands out to me is the noise goes away when i drop the rear shaft. This leaves me to believe that the issue may be w/ the welded rear.
other thoughts: i had two other cruiser folk look at it and one believes its and exhaust leak and or rattle, the other thinks its in the t-case/tranny. I do have a leak at the union of downpipe and exhaust manifold, but after 1/8th mile of wire wrapping i feel it is not a exhaust rattle. now whether its me hearing the exhaust cylinders open/shut i dont know, but i doubt it.
With the noise gone when i pull the rear shaft, could this be a broken spider gear weld? or worse? I wouldnt think it would be intermittant and speed variable if something was floating around in the diff.
Thanks in advance guys and sorry for the mini-novel. I do plan on putting her up on stands and dropping the diff cover for a looksee when the rain stops.
IH8GRAVELDRIVEWAYS
Vehicle: 72 FJ55, SOA w/ a BL as well, 1 F motor, 4spd w/ a three speed t-case, front disc axle, saginaw steering, WELDED REAR, and some sweet chatanooga cruiser custom van seats.
HIstory: Ive had the cruiser for a year now and have redone the PS system as well as the clutch now, and then just small issues beyond that.
Issue: Last fall i had intended to tow the pig to the Pumpkin Pig Run in the NC mtns. Well when the towrig plans fell through i dove in the day of departure and changed all fluids (motor,diff, tcase,tranny, and brake as well) checked the nuts and bolts, crossed my fingers and headed out. 7hrs later i was there, but the issues had begun. On the climb to the cont. divide on I-40 i started to get a knocking noise only in the higher end of rpm band. I stopped and rested but being 5.5hrs in i continued on. I got a couple days of trail in before it appeared the clutch was not holding for the hills, so i got out while i could and had the pig towed home.
sorry, so the issue is a pretty loud knocking noise as i get up to speed more than up to rpm. the symptoms occur in first while accelerating, second not so much, third ABOVE 40 ONLY, and fourth gear ABOVE 50mph only. You can put as much load as possible on drivetrain, but it will only occur once up to these speeds? once at 50mph in 4th you can let off and it goes away and when barely feathering the gas (if still at speed) it comes right back, no hesitation, w/ very little load on the system. It does not happen while revving engine in neutral. I can feel a knocking in the t-case by touch while driving. Starting to believe it might be a t-case issue but it will still Knock in nuetral, with the clutch in??
What ive done: I inspected clutch for a bolt backing out of the pressure plate, no luck, but i went ahead and replaced the whole clutch assembly. I dropped each drive shaft and inspected U-joints (they feel good to me, but ive never felt a bad one) but they do not have excessive play. The key fact that stands out to me is the noise goes away when i drop the rear shaft. This leaves me to believe that the issue may be w/ the welded rear.
other thoughts: i had two other cruiser folk look at it and one believes its and exhaust leak and or rattle, the other thinks its in the t-case/tranny. I do have a leak at the union of downpipe and exhaust manifold, but after 1/8th mile of wire wrapping i feel it is not a exhaust rattle. now whether its me hearing the exhaust cylinders open/shut i dont know, but i doubt it.
With the noise gone when i pull the rear shaft, could this be a broken spider gear weld? or worse? I wouldnt think it would be intermittant and speed variable if something was floating around in the diff.
Thanks in advance guys and sorry for the mini-novel. I do plan on putting her up on stands and dropping the diff cover for a looksee when the rain stops.
IH8GRAVELDRIVEWAYS