I have a new to me D7F with a Hyster Winch on the back. Problem I am having is when you fill the Transmission to the proper level and the machine warms up to the high side of green on the coolant gauge. The winch starts puking oil out from around bolts and plates that are bolted on. We have pulled the bolts found a few holes are oblong. We replaced with new bolts and washers and as long as the trans is cool the leaks are small, as it heats up she leaks more. What I want to know is there away I can Isolate the Hydraulic lines to the winch?
Do NOT isolate the hyd control pipes to the winch. The clutch packs need that oil for cooling and lubrication. Everytime engine is running pinion and bevelgear shaft in the winch is turning, even though winch drum may not be turning. Is the winch overfull with oil ? Is a level plug on either right or left side of winch, remove it and let any excess oil run out to the plug level. Also sometimes covers on the winchs get damaged from abuse. You may have to remove the cover and reseal it; or panelbeat it flat and true first and then reseal it. Case cover in front of winch drum is a classic for this from people trying to drag rigging through the winch case !! One other thing, is this leak in the centre of winch where winch bolts to tractor ?? is 2 internal nuts in the winch these studs need O rings on them BEFORE winch is fitted, otherwise it will leak
The winch has a 3/4 inch hydraulic line on the left side and a 2 inch line on the right side. The winch will leak oil when the engine is shut down. It is leaking from the plate between the drum and the back of the machine and now from the plate that is on the right side of the drum, (it is angled upwards)Is there a seal that is blown and pressurizing the winch body? I would be just as happy to pull the winch off and be done with it, any idea how much work there is to pull the winch off?
big pipe is suction line to pump, smaller pressure line to winch. angled plate on rh side is main cover over winch gears, as stated earlier easier to remove and reseal plates first. Winch can be removed in a day, that centre cover has to come off anyway to get access to the 2 internal studs. Have to remove hyd lines and pump. AND will need 2 covers and gaskets, one for pump and other for pto shaft hole. Winch should have a threaded hole on each side for lifting, will weigh 2 ton. Handy things to have for pulling stuck machines out; half of my herd have them ! Hyster winchs are quite solid, better than the cat ones of the same era.
Yair . . . . bvwaste I don't know if you have run a bare assed tractor but I reckon a winch or rippers makes a difference to the balance, I'd leave it on there if you can. Cheers.
Well, we pull the plates and seal things up and see what happens. Will keep you posted
don,t be shy, put up a pic too; dozer not you :drinkup
This is our D7F S.N. 94N3889 had engine, trans. and final drives rebuilt in 2000 and was parked. Had 250 hours when it landed here from Campbell River area of British Columbia. I have bit the bullet and called the Cat mechanic to come out today and fix the leak.
When you had the RH cover off, where the 2 hyd hoses inside the cover at the bottom end ok ?? one is lube supply other rev, .Rev only has pressure in it when unwinding, but lube is live all the time. If its blown oil will spray all over the place internally and may be too much for the cover to handle. With the winch not being in gear [fwd or rev] drum gears aren't turning and they don't throw up any oil to leak from that plate. Was plate flat and true ?? Not much else that can make it leak on the outside. Sure it wasn't overfull ?? Tidy looking 7F; quite straight for a 40 yr old machine esp a bush rigged one.
Pulled winch, 1 man 5 hours. Bearing on the front shaft was gone which tore up the seal, causing the Transmission to pressurize the winch. Lucky part, no bearing pieces got into the machine, bearing failure was caught in time. Now to fix everything. Yes Merv, it is in nice shape and has had a good life. I plan to keep her that way.
pay to pull clutch shaft too then as its turning all the time along with the input shaft. Other shafts only turn when its put into gear; fwd or rev. Lucky no toothache. People think cat parts are expensive, hyster parts ARE made of gold in comparison
Will be looking at that in the morning. Thanks for the tip
Update on the saga, employees over filled the transmission by 30 liters (6 gallons) which made a small leak on the left hand side final drive a big leak. Split the track, pulled the track frame and sprocket plate. Replaced seal, bearing and race, ran the machine in the shop with the sprocket turning to check for leaks. No leaks, put everything back together, changed all the fluids (final drives, transmission) changed the transmission filter. Pulled it out of the shop to mount C Frame and machine will turn left, but not right. When you pull the right lever and step on the right brake the machine stops altogether. Any Ideas??
Machine steered fine when I ran it up to the shop and backed it in. Only problem at that time was the leaky left final drive.
Excellent news, problem was a sticking spool valve under the seat, finally a lucky break. The seal job took more time than I liked, but all is well