Clutch Chatter When Warm/After Highway Driving

[michaelkersch]

I recently bought a 1980 Scout Turbo Diesel. It runs great around town. It runs great on the highway (geared to high though). But, when I get back into town after driving long stretches (hours) at highway speeds I get clutch chatter letting it out in 1st gear and worse going into Reverse. It's fine once I get past 1st. I have the t-19 4 speed wide ratio I believe, becasue I can only do 5 mph in 1st. Just put in new straight 50 weight oil, but no difference, and rest of the oils are topped up.

It also seems to smoke a lot at cold start and will smoke longer if I stay stationary, if I start driving it seals up faster and stops smoking. Don't know if this could be related.

Any thoughts?

-Motor mounts? (it shakes a lot at idle compared to my 345 V8, but I think that's normal)
-Clutch going out?
-Bad bearing that gets stressed at speeds? (Maybe leaks oil to the clutch plates?)

Thanks in advance, I love the knowledge circulating here!!

[Jay Tabor]

crawl under it and look for oil on the flywheel;
most likely its hard spots on flywheel face, and or pressure plate,too.
worn engine mounts can cause similar symptoms
a simple clutch test finds the cause=
engine running -warm
e brake on tight- car pointed at wide open space

right foot heel on brake, toe on throttle pedal.
left foot on clutch pedal.
depress clutch engage 1st gear
rev engine to 1500
let go of clutch pedal fast
does engine keep running-
hearing all sorts of slipping spinning noises as it slows down

or does engine stop abruptly?
do same test in reverse-
all the while have hood up and see how far engine torques when clutch pedal is released.
little to no movement of engine = good condition mounts.
immediate stoppage of engine= good clutch.
dont forget to check trans mount .

[michaelkersch]

Thanks for the concise instructions. I'll do so when I get a chance. It just perplexes me a bit why it would only happen after a lot of highway driving. Is it possible that a bearing or engine/trans mount would act normally around town but then get stressed/hot and loose after highway miles?

M

[bluescout]

On the clutch, like he said it's probably hot spots. On the smoking, they skip when they're cold and warm up faster when you work them and also, if the turbo or valve seals are dripping a bit of oil, it'll go away faster if it heats up fast.