Exhaust valves chipped

Polarice

New member
I had my exhaust valves cleaned on my older '07 IQ HO 600. The guy that cleaned them said there was a chip out of both of them. He couldn't understand why.

Has anyone heard of this?
 

Polarice

New member
I just got these back last night!

Does anyone know why this happened? Thank the Lord that these did not damage my pistons. valves.jpg
 

Polarice

New member
A chip! that is a understatement to say the lest.where is the rest of them? I could not sleep till I found every piece

That's what I thought. He looked at the pistons and there's not a scratch. Said it went out the exhaust. He's seen this before but just not on the stainless exhaust valves.

This may have happened early in the season for all I know and I ran it like this all season.

I want to know why and how this could've happened.
 

thebreeze

Member
I would love to see the tops of your pistons, and head. Hopefully there was not too much damage when they exited the engine, but there has to be some pretty good dents in there. Id throw the compression gauge on there, and pull the valves, and spark plugs, and visually inspect the piston crowns with a small light down the spark plug holes. I would be very wary of just givin er after seeing those valves. The pieces are probably scattered along the trail somewhere. If it makes you feel any better, the pieces likely stayed out of the bottom end.

edit: Just saw that the mechanic inspected and saw no issues.
 
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Polarice

New member
I would love to see the tops of your pistons, and head. Hopefully there was not too much damage when the exited the engine, but there has to be some pretty good dents in there. Id throw the compression gauge on there, and pull the valves, and spark plugs, and visually inspect the piston crowns with a small light down the spark plug holes. I would be very wary of just givin er after seeing those valves.

He did all that. Nothing there.

Good lookin' valves eh?
 

thebreeze

Member
Pretty sweet indeed. I don't know what could cause that, other then the valves chattering inside the passages, or contact with the pistons. Contact with the pistons would not have only chipped one side IMO, so I would rule that out.
 

Dave_B

Active member
Holy Waa!

I would blame the guy you bought it from! He obviously didn't take very good care of it!

I hope you get it back on the trail soon and not have to spend a fortune!
 

Polarice

New member
Holy Waa!

I would blame the guy you bought it from! He obviously didn't take very good care of it!

I hope you get it back on the trail soon and not have to spend a fortune!

Haha! I won't blame the guy I bought it from, I know how these things can be. It was around $200 to get them fixed. I think the thing has almost 7000 miles on it. It's all ready to go, we just need some snow!
 

snowbuff

New member
Imo, what happend is at some point before you bought it, the piston and/or ring hit and broke them (maybe bad gasket) then the guy replaced the pistons & rings and just put it back together. He may have not even noticed the broken valves. He may have had damage to the head as well and just replaced or repaired it. I don't know any other way that could happen without any other damage.
 

Dave_B

Active member
Imo, what happend is at some point before you bought it, the piston and/or ring hit and broke them (maybe bad gasket) then the guy replaced the pistons & rings and just put it back together. He may have not even noticed the broken valves. He may have had damage to the head as well and just replaced or repaired it. I don't know any other way that could happen without any other damage.

For the record, he bought it from me. Before I sold it to him, the exhaust valves were clean and the machine ran like it was new. I never had any issues with the valves or pistons while I had it. It ran great and was always serviced according to what was recommended from the Manufacturer. When I sold it, It had over 5,000 miles on it.

I was joking in my previous thread and, if there was anything wrong with it, I would have told him. He has had it gone through before after he bought it, and I don't remember him telling me any issues with the valves.

My point is, I wouldn't sell anybody a sled with the problems and "fixes" you mentioned. I'm sure he is confident that he bought a 5,000 mile sled in the best possible condition it could be.

Dave
 

Polarice

New member
Imo, what happend is at some point before you bought it, the piston and/or ring hit and broke them (maybe bad gasket) then the guy replaced the pistons & rings and just put it back together. He may have not even noticed the broken valves. He may have had damage to the head as well and just replaced or repaired it. I don't know any other way that could happen without any other damage.

I had the valves gone through after I bought it as Dave mentioned. Even the old man who cleaned the valves last year didn't see anything like this.

The only thing I can think of is that it has the high mileage and they just wore out.
 

rp7x

Well-known member
smokin hot

i'd check yor carb boots they do rip apart , could cause it to run lean and burn them away , have you run any race gas or av gas ? race gas burns slower and could still be burning going out the pipe
 

Polarice

New member
i'd check yor carb boots they do rip apart , could cause it to run lean and burn them away , have you run any race gas or av gas ? race gas burns slower and could still be burning going out the pipe

Carbs were taken off and cleaned during this maintenance. Didn't see bad boots. I'm thinking I should just replace them anyway due to the mileage.
 

polarisrider1

New member
OMG's I have never seen exhaust valves that looked llike that and I have seen many. They look like they were put in a vise and wacked with a hammer. If they did that in the motor the motor would be toast. No way can chunks of any size make it thru any part of a Poo motor or it's exhaust without damage a plenty. Chipped? are you that naive?? I smell a Rat. Dave B. would never sell anyone something that is not working correctly. Is this an April fools in Dec.?
 

Polarice

New member
OMG's I have never seen exhaust valves that looked llike that and I have seen many. They look like they were put in a vise and wacked with a hammer. If they did that in the motor the motor would be toast. No way can chunks of any size make it thru any part of a Poo motor or it's exhaust without damage a plenty. Chipped? are you that naive?? I smell a Rat. Dave B. would never sell anyone something that is not working correctly. Is this an April fools in Dec.?

This is not a joke. The mechanic said that they were chipped and I had to wait for the parts to come in. It held off from me picking it up. When I got there I said the same thing about a chip. I said they're half gone! He said; well they're not Half gone.
 
CHIPPING vs. BREAKING

Carbs were taken off and cleaned during this maintenance. Didn't see bad boots. I'm thinking I should just replace them anyway due to the mileage.

BTW, if those are CHIPPED I'd like to see what you refer to as BROKEN valves, LOL.

Regarding the exhaust valves, it sounds like the "stops" int he jugs themselves are worn (due to the miles on the sled) and it allowed the valves to contact the pistons , and thus the resulting "chipped" exhaust valves.


There are 3 options;

1) LIGHTLY grind the new exhaust valves to clear the pistons with a margin of safety

2) Send the jugs to MILLENNIUM TECHNOLOGIES in Wisconsin, as they "rebuild" the "stops" in the jugs themselves.

3) Re-install new valves, and wait for the same thing to re-occur again shortly, next time resulting in possibly more "chipping" and domino effect of broken, or what you may refer to as "chipped" pistons, and / or cylinders.

The carb boots are only $ 50 so I HIGHLY recommend replacing them as preventive maintenance. Sometimes you can only find the rips by having the boots on the workbench and flexing them to inspect.


Hope this helps
 
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