Need A Repair Manual...

[Stoneman]

I've got a line on an old dog, ancient really. And almost free...

I know a dude that's got a '87 YZ250 2-stroke. Wunna the early liquid cooled jobs. His head gasket shit the bed on him last year (or so he thought), so he pulled the motor and replaced it - the gasket (them really, it's just two little O-rings) over the winter. He took it out for a test ride Saturday, drained the erl, and found coolant in the erl AGAIN...

So I'm thinking if I can get my hands on a downloadable repair manual, I may just have an incredibly cheap dirty beater. I won't take it off his hands just for the sake of doing so. But if I can track down the fix, it just may end up in my garage this weekend...

[Wishbone]

Motorcycle Repair Manuals Club



Viewing Motorcycle Service Manuals - Go Fast Video :: 100mbits of Free Racing Videos

[Stoneman]

Maybe I'm not seeing it, but mosta those sites don't have anything for something that old...

[ChR1s]

Coolant in the oil? It's a smoker. The gearcase oil's only for the clutch & gearbox. Water jacket only goes through head & cylinder? Not sure how that'd happen.

And a little FYI. Many parts that old are no longer available through Yamaha.

[TheIglu]

I got an '82 with the same engine. I also have the manual. If'n you need some photocopies, let me know.

[Paul_E_D]

Waterpump needs rebuild. Check for parts availability. That thing will need it all, shaft, seals, bearings.

[Paul_E_D]

Actually, there's one more serious possibility, and that is that hte crank seals are shot. That's a split the cases affair. It would have some funny running symptoms though. If it runs perfectly, just pukes water in the oil, it's the waterpump.

[Stoneman]

I got an '82 with the same engine. I also have the manual. If'n you need some photocopies, let me know.

'82 & '87's had the same engine? Holy shit!

I'd like to see the layout of the cooling system. Any chance on scanning 'em & emailing 'em?

[Stoneman]

Paul-To the best of my knowledge, it's running fine. He dumped the oil to see if he was still 'losing' coolant. Low & behold, there it was...

First thing I mentioned to him was the water pump. I thought maybe the bearings on the impeller shaft could be beat and/or the seals (more so, the one behind the water pump)...

What about a cracked head?

I'm stopping by to look at it today...

Thanks!

[Stoneman]

Called around to a handful of local places today. Suprisingly, parts are still fairly easy to come by. Most parts I inquired about'll take 10-14 days to get...

[ChR1s]

How is the water pump lubricated with gearcase oil? I just don't see it. A blown crankcase seal will cause HUGE amounts of smoke, and lots of gearcase oil consumption. I know of a guy that tore his RM's engine apart a couple of times in an attempt to rid the oil of taking on water/coolant. What he'd failed to realize is that the oil gets to looking quite funky right after use due to clutch fragments being suspended in it -- the oil was in fact fine, as was the engine.

[Paul_E_D]

I'd have to study my manual, but the waterpump shaftruns through the right side cover into the clutch housing, which is full of...oil. When the seals go, usually accompanied by wear to the shaft, the water enters the clutch housing.

I just went through this on my KDX. Remove right side cover, bang out bearings, replace seals and use a new shaft. No more water in oil.

[Stoneman]

He insists that the oil is tainted with coolant. I haven't seen it yet, I will later today though. He says that he's losing coolant, not just getting the oil contaminated...

I'm almost certain if that back seal (behind the water pump) is leaking, the coolant will get into the oil...

[Stoneman]

Yip, was the seal on the back side of the water pump...

POS though. Don't even wanna bother...

[Rye]

I thought you already owned a badass Honda?

[OreoGaborio]

he did, but he sold it to me for 100 bucks

[Stoneman]

I thought you already owned a badass Honda?

I'm still waiting for the new, clean, street title on it. You wanna buy it? I've only REALLY got like, 60-something beans into it now. Then I got this piece of paper that says I bought it for $1500. But it's all set up for the street & good to go. We should talk...

[OreoGaborio]

You drive a hard bargain, Jay.... but ok... how's 1600 sound?

[Rye]

Sold!