Replacing 540 pistons- spilled coolant down in case

VMAXMARK · Post by **VMAXMARK** » Mon Sep 21, 2009 1:02 pm

I'm getting ready to replace the pistons and rings in my '85 VMAX and during disassembly I spilled some coolant down in the crankcase.

I was able to use my small shopvac and stick the nozzle down inside and suck out the coolant and I dont see anymore in there but will the residual coolant cause any problems?

If so how do I clean it out?

thanks for the help

vmax-540 · Post by **vmax-540** » Mon Sep 21, 2009 4:04 pm

I would get as much out as you can and as long as there isn't any puddles of coolant in there I think you are OK just oil it up good and get it running as soon as you can , you should be OK..

VMAXMARK · Post by **VMAXMARK** » Tue Sep 22, 2009 7:43 am

OK- thanks

Bob Vehring · Post by **Bob Vehring** » Tue Sep 22, 2009 10:41 am

Now days most parts stores or places like Harbor Fright sell the small Vacuum pumps, people use them for draining oil in boats or lawnmowers. There 2-3 ft tall, round usually and have a handle like a bike air pump. They have a 1/4 in hose that you can push down in the case and pump, it will suck out anything, you can use a little solvent to clean things up down there and suck it all out. We use these all the time for all kinds of jobs, I even use it after cleaning the sled to get all the water out from under the engine

VMAXMARK · Post by **VMAXMARK** » Tue Sep 22, 2009 4:01 pm

Ok- I have another question- what is the "infamous waterpump seal" problem I read about and is it only the 1983's?

vmax-540 · Post by **vmax-540** » Tue Sep 22, 2009 4:27 pm

The problem with that seal is it leaks either anti-freeze into the gear case or gear oil into the anti freeze or both . When Yamaha came out with the 81 SRX it was a "NEW"engine and the seal and water pump shaft was a bad design, Yamaha had an updated shaft as a fix but it wasn't much better. When they came out with the 83 Vmax they had the same problem with it. In the 84 and up models they came up with an "All" new seal, shaft, and just about all the other parts that are in there,that was a BIG improvement and for the most part the problem was solved,but even the 84 design has a problem once in a while . My advise to anyone with an 81 SRX or 83 Vmax is to use the 84 & up water pump. The biggest problem now is that is the seals for "ALL" years are no longer available from Yamaha so you have to find a NOS some place or use double seals in them like is explained in one of the posts here in the forum.

VMAXMARK · Post by **VMAXMARK** » Wed Sep 23, 2009 7:52 am

Thanks for the info.

Are there any other common problems with these sleds that I should be aware of?

Post by **tyler440** » Wed Sep 23, 2009 8:14 am

ive seen a decent amount of problems with the thermostat.... i actually damn near melted my engine into a puccle of aluminium because it stuck closed somehow (in the middle of the ride) i suggest gutting it and only putting the housing in there... it will take a bit more to warm up before you go smashing the gas but i havent had any issues since.... as with any motor you should allow it to get to operating temp before you go running it hard... the piston will expand faster than the cylinder and if you hammer on it too soon the piston to cylinder clearance willl dissappear and "cold seizing" will appear on the piston skirt and cylinder wall