New Project: 1997 Yamaha VMax 700 Triple

9

97vmax700triple

New member
Joined
Sep 22, 2016
Messages
23
Location
Adirondacks, NY
I picked this thing up as a project. The previous owner ran it hot, to the point where the redhead cylinder head is now black on the far side.

I was able to start it, and it actually idled pretty good considering how long it had been sitting. However, there was coolant pouring out between the third cylinder and the head.

I ordered three new top end head gaskets and plan to resurface the head. The cylinders and pistons look fine and the head isn't cracked.

Anything else to watch out for on these sleds? I heard the crank bearings suck on these. Hopefully I can get a few years of use out of it with only 1500 miles on the odometer. This is also my first sled, and I picked up a service manual to help with the repairs.

Thanks for any help, much appreciated.
 
Nothing wrong with the crank bearings on the red head triples. 97's had ball bearings and 98 on up had the roller bearings which are a little better. I've had mine for almost 20 years now and never had any issues. With that low of miles that thing must have sat for quite some time, hopefully the engine was fogged, if there is any rust on those crank bearings it might not run too long. There really isn't anything major you need to watch out for, just check the W arm in the rear suspension for cracks, it's common with all proaction sleds. Make sure you keep the carbs clean, should be cleaned every fall. I'd also flush and fill the coolant, if you do flush make sure you use distilled water. I run honda hp coolant in mine, the hp coolant has no silicates in it which can eat up your water pump seal.
 
Most likely a coolant issue to turn that red head black. Odd that it only partially discolored the head based on your description. Dont think I have ever seen a burn down discolor a head. My concern would be the crank bearings. If coolant got down low and wasnt immediately addressed, you may have a ticking time bomb on your hands. The cheap fix is now, before the potential blow up.

There were some crank bearing issues on the 97's, that why Yamaha updated them i 98. Not enough problems for a recall, but enough to prompt a service bulletin along with the need of an upgrade in 98.

Make sure that the head isnt warped and dont take too much material off the mating surface if it is. If you need a 97 head, let me know. I have one new. Be aware, the 97 head did not have the provisions for carb heat as that year sled didnt have it. You may consider that as an upgrade as there must have have been a reason it was added on the 98 and up models.
 
MrSled said:
Can we see some photos? Black Heads Matter..LOL
Click to expand...

I need to clean it first. It was rescued from storage and is covered in dust.

snowdad4 said:
Most likely a coolant issue to turn that red head black. Odd that it only partially discolored the head based on your description. Dont think I have ever seen a burn down discolor a head. My concern would be the crank bearings. If coolant got down low and wasnt immediately addressed, you may have a ticking time bomb on your hands. The cheap fix is now, before the potential blow up.

There were some crank bearing issues on the 97's, that why Yamaha updated them i 98. Not enough problems for a recall, but enough to prompt a service bulletin along with the need of an upgrade in 98.

Make sure that the head isnt warped and dont take too much material off the mating surface if it is. If you need a 97 head, let me know. I have one new. Be aware, the 97 head did not have the provisions for carb heat as that year sled didnt have it. You may consider that as an upgrade as there must have have been a reason it was added on the 98 and up models.
Click to expand...

I'll let you know about that head. I haven't checked it for straightness yet, still waiting on the gaskets to come in the mail. Hopefully by next weekend I can put it back together and see how it runs.
 
you said you started it before you tore it down. I wonder if you will be able to tell if there was any rust on those bearings now it has been started. Or the real amount of rust there was before running the engine. Just fuel for thought. I could be wrong.
 
I have it all back together. After a brief smoke show from some oil on the header, it idled great. I ran it for a few minutes and the motor sounds healthy. No more coolant leak from the head, either.

I noticed the track doesn't engage when you rev it up, though. I had the motor up to like 5k and the track didn't move. I could move it by hand a little bit, but there was a lot of resistance. So I guess that's next to look into. Any ideas?
 
well the primary spins with the motor, and I'm able to turn the secondary by hand which moves the track. For some reason it seems the belt isn't transferring power from the primary to the secondary.

Also the water pump housing is dripping coolant. I bet this is why it overheated in the first place.
 
Is the primary rusted at all or black and full of belt dust?? Water pump leak means you have to replace the mechanical seal in the water pump.
 
Primary "spins with the motor" and thats it?, or do the sheaves actually move at rpm? Big difference as its centrifical force that makes the movable sheave move towards the fixed sheave and engage the belt. Stuck or binding clutch wont engage. You need to pull the clutch off or at least pull the cover off and run it through the motions.

Weeping pump wouldnt cause the overheat but a lack of pre-ride inspection(no coolant visible in the overflow) would.
 
snowdad4 said:
Primary "spins with the motor" and thats it?, or do the sheaves actually move at rpm? Big difference as its centrifical force that makes the movable sheave move towards the fixed sheave and engage the belt. Stuck or binding clutch wont engage. You need to pull the clutch off or at least pull the cover off and run it through the motions.

Weeping pump wouldnt cause the overheat but a lack of pre-ride inspection(no coolant visible in the overflow) would.
Click to expand...

The coolant bottle was empty when I got it, so it definitely was run low on coolant.

I still need to look into the clutch.

I noticed the coolant bottle is milky, so oil is definitely mixing with coolant. I think that water pump needs to be rebuilt. Has anyone done this before on these motors? I have the service manual but forums ftw!

Thanks for the replies, appreciate it. Hopefully we get a good amount of snow this year.
 
I'm going to order the parts and rebuild the water pump mechanical and oil seals. Is there anything else I should r and r while I'm at it? Farmers Almanac has a major snowstorm just over a month away!
 
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