2000 MXZ 700 Engine went this past weekend

[lofsfire]

So I was up in Cadillac this past weekend and had a issue with my sled. I took it apart last night and here is what I found:
Pitting on Head and Piston. So it look like I will need a new head, piston and honing ((see Picture)I hope) on one jug and maybe something in the crank. Everything seams to spin fine now that it is apart, but the Clutch side seemed to come up just a little higher than the top of the Jug when I removed the head. And the Piston was defiantly hitting the head. Take a look at the pictures and tell what you think.

Head

Clutch Side Head

Recoil Side Head

Clutch Side Jug Exhaust side
How bad does that black line just off center of the bolt hole, look? If you rub it you can feel it slightly.

Clutch Side Jug Intake side

Clutch Side Piston

Then to top all this off as I was taking out the head bolts one snapped off in the other Jug that has nothing wrong with it. Looks like it will come out easy enough but it always has to be something. Right?

I have a friend that is a mechanic that is going to look at it this weekend and tell me how bad it really is. We will see....

Oh by the way my sled has 8,360mi on it. Would you fix it or part it out?
If I part it I'm done for the year maybe next year also. Ideally I only want two more years out of this sled then would have wanted to get something new or newer. I'm thinking 4 stroke now!

 

[doo_dr]

The pictures only show that something broke loose and started to rattle around. It could have been:
Piston ring keeper pin
wrist pin circlip
thrust washer on lower rod bearing
something from the reed cage
part of the bottom of the piston skirt

Just from these possiblities I would look at it like a short block exchange and labor to install versus the value of the sled in running condition. I don't know your market but I would say $1000+ labor(free, my own) versus a sled for sale in February (maybe $2500 in great shape). Look into deaper before you make the call as I see a possible crank issue and they are not cheap in any fashion

 

[awickman]

I am in the same boat. 2000 MXZ 700 with 10,000 miles. Rod bearing gone out of it. Top end looks good as it was rebuilt about 2500 miles ago. New reeds and mechanically in great shape. Have a 06' MXZX 600 SDI that i normally ride but had this for when the wife wanted to ride. Ski-Doo remaned crank is $450. The way i look at it is i do that and even new rings so a total of $600-$700 buck and you know what you have. You go buy a used sled and might ahve to go thru the same thing in a short time.

 

[ezra]

part it the crank is next you are already on borrowed time on the crank.worth more in parts than running

 

[doomsman]

The head can be cleaned up, the jug will work. I agree take it down to bare case and inspect the crank, new seal and a pair of pistons and ride it.

 

[dab102999]

Yea that head will clean up for sure. Emory cloth and scotch brite.Take the motor the rest of way down before you decide anything. Miratic acid (or however you spell it) in the cylinders to take the alum out. {take it easy with that stuff if you don't know what you are doing}That scratch you feel is probably alum build up. Those cyl are hard to destroy. Once you get them cleaned up you will be better able to see or feel a scratch. But take it all the way down, it ain't runnin now anyways. If your crank is still good re-pack the bearings with iso flex ($100) and put new seals in it. A good complete seal kit will be around $80 but will do entire motor. If you don't need a crank could do this motor for around 3-4 bills easy. Probably a little cheaper. If you need a crack a re-man from doo is $450 and grease is $100 so I would opt for the fat bearing greaseless one by doo clinic for $600. Check out mcb performance, they got some pretty good prices on stuff also. They are the cheapest I have seen for jugs if that is what is needed also.

 

[lofsfire]

Thanks guys I have been finding all of the same thing as above from friends that have been down this road before. Should know more next Monday. I will keep you posted.

 

[lofsfire]

Ok, I took it all apart and found out the bearing on the Clutch side was in pieces. So I have to find a new one or rebuild mine. Any suggestion on where to get one?
I plan on calling a two local place tomorrow, but from what I have heard they are back logged 1+ months to rebuild.

 

[dab102999]

Give me a part number, I have an extra one that I bought for mine to rebuild when I found a crank instead. $60 or so from the dealer, I got mine for $30. You can have it for that if you want. I believe my pt # ends in 601 but would have to look for sure.There is a crank guy down by you that I have used in the past. Can't remember his name off hand but I remember that he replaces a bearing and checked the crank for true (with me supplying the bearing) for like $50.

 

[snootbiscuit]

if crank bearings have plastic keepers, have crank rebuilt w/ new metal caged bearings!!

 

[lofsfire]

Give me a part number, I have an extra one that I bought for mine to rebuild when I found a crank instead. $60 or so from the dealer, I got mine for $30. You can have it for that if you want. I believe my pt # ends in 601 but would have to look for sure.There is a crank guy down by you that I have used in the past. Can't remember his name off hand but I remember that he replaces a bearing and checked the crank for true (with me supplying the bearing) for like $50.

I will let you know, Thanks for the offer. If you think of the number of the guy in my area please let me know also.

if crank bearings have plastic keepers, have crank rebuilt w/ new metal caged bearings!!

I will double check.

 

[lofsfire]

dab102999 I think we are talk about two different bearings, sorry I probably was not very clear before. The bearing I'm in need of is the PTO side rod bearing. But thank you for the offer!


I'm looking at $450 (locally rebuilding mine one month turn around) or $550 to $650 from Doo Clinic and about a week turn around. Plus I need a full engine gasket kit ($200 From Doo less aftermarket) and one piston ($150 From Doo less aftermarket). At minimum that $800. Big question is it worth that to me or part and try to talk the wife in to and newer one next year.

Any thought and aftermarket parts?

 

[dab102999]

crank $450 straight from doo (rebuilt) plus $100 for grease or $600 from doo clinic and these should be fat bearing no grease ones. [At least for an 800 that is the price.] Gasket kit, cometic $80 complete. Everything you need. Pistons buy two since you are doing it. In fact mcb has two pistons and gasket set for under $300. I would think they would have them for a 700 also. If you need a jug it is around $200 from them. As far as aftermarket I wouldn't be afraid of it at all. SPI makes a good piston. In fact I have the two ring pistons from mcb in my 800 and am really impressed with them. As far as rebuild, that is your call. What shape in the machine in?? How close are those kids to being ready to ride it?? How good is the track,shocks, and skis?? If all that stuff is getting ready to go then I would say scrap it and move on.The way it is, without seeing it is probably only worth around a grand or so on a good day.
I went through the same thing this year, toasted my 01 800 at the end of the season last year. Went back and forth on rebuilding it and selling my 97 vmax or sell it and keep the vmax. Sold the vmax, tossed in another $50 and it rebuilt my 800 and I have a suspension that is 4 years newer. My 800 has 9500 miles on it and now it is all tight again.
If you rebuild don't skimp on parts though. Last year I put a top end in the 800 to freshen it up and thought about checking the crank but thought...oh I am o.k. there and .....well you can see how that turned out. Put $300 in it last year to save some cash and ended up redoing what I did and more...

 

[doo_dr]

The pictures only show that something broke loose and started to rattle around. It could have been:
Piston ring keeper pin
wrist pin circlip
thrust washer on lower rod bearing
something from the reed cage
part of the bottom of the piston skirt

Just from these possiblities I would look at it like a short block exchange and labor to install versus the value of the sled in running condition. I don't know your market but I would say $1000+ labor(free, my own) versus a sled for sale in February (maybe $2500 in great shape). Look into deaper before you make the call as I see a possible crank issue and they are not cheap in any fashion

I wasn't too far off from the beginning. Part it out and save $'s for an upgrade next year. You probably have people watching right now that will E-mail you requests for some of the parts on your sled.

Good Luck which ever way you go!!!!

 

[lofsfire]

crank $450 straight from doo (rebuilt) plus $100 for grease or $600 from doo clinic and these should be fat bearing no grease ones. [At least for an 800 that is the price.] Gasket kit, cometic $80 complete. Everything you need. Pistons buy two since you are doing it. In fact mcb has two pistons and gasket set for under $300. I would think they would have them for a 700 also. If you need a jug it is around $200 from them. As far as aftermarket I wouldn't be afraid of it at all. SPI makes a good piston. In fact I have the two ring pistons from mcb in my 800 and am really impressed with them. As far as rebuild, that is your call. What shape in the machine in?? How close are those kids to being ready to ride it?? How good is the track,shocks, and skis?? If all that stuff is getting ready to go then I would say scrap it and move on.The way it is, without seeing it is probably only worth around a grand or so on a good day.
I went through the same thing this year, toasted my 01 800 at the end of the season last year. Went back and forth on rebuilding it and selling my 97 vmax or sell it and keep the vmax. Sold the vmax, tossed in another $50 and it rebuilt my 800 and I have a suspension that is 4 years newer. My 800 has 9500 miles on it and now it is all tight again.
If you rebuild don't skimp on parts though. Last year I put a top end in the 800 to freshen it up and thought about checking the crank but thought...oh I am o.k. there and .....well you can see how that turned out. Put $300 in it last year to save some cash and ended up redoing what I did and more...

doo_dr
I wasn't too far off from the beginning. Part it out and save $'s for an upgrade next year. You probably have people watching right now that will E-mail you requests for some of the parts on your sled.

Good Luck which ever way you go!!!!

Both you you guys have been right on the money. Thanks for the advice from everyone as of now I'm still debating on what to do. If I rebuild it I'm going to do it right with the fat bearings on the crank, a set of pistons. This also means I will keep it for a few more years. As far at the Sled condition there are some pictures from last year below you can see it is very clean. Only problem areas are wear items. Track has 3 lugs off but that happened 3 years ago. So its still good. I probly should rebuild the shocks, but it rides great. So I have not. And of course there is that ugly exhaust cover that breaks on Doo's,but that is cosmetic. Other than that stuff, it will keep up with the new sleds all day long. Well normally, LOL!

The kids won't be riding for a few more years. My oldes is 6, next one is 3 and the youngest it 2.5mo. I need a snowcoach for them right now.

track picture is 3 years old 3lugs are missing

My MXZ 700 and my wife's ZL 500 with low miles and just as clean.

 

[lofsfire]

So if I were to look for a new sled what would you recommend?

I would most likely look in this in this brand order. No preference on model order.

Ski-Doo
MX Z X-1200 4-Tec
MX Z X-800R
MX Z X-RS 800R
GSX Limited 1200 4-Tec

Yamaha
Apex GT
Apex
FX Nytro

Cat
Z1 Turbo
Z1 LXR

What is the maintenance like on the 4 strokes?

What time of year is the best to buy?
Now
Spring
Fall

 

[notaboveme]

Must be something in the water. 3 years ago my daughter blew up my 01 MXZ 600 on the straight away outside Boon. Still hauled it to Drummond the next weekend and put 350 miles on it on one cylinder, top steep 62 MPH. Coolant leak on the jack shaft blew a hole in the piston. Bored out and new pistons and 1500.00 later all is well, it is faster than ever!

 

[lofsfire]

Ok so even with as much as I want a new sled, after really sitting down and looking a the cost of new and the cost to rebuild this one, I just cant justify a new on at this time. I rather build a great engine and have money left for a snowcoach or something like that. That way I can take the kids along too.
I figure I will do the engine and cluch right now, have the shocks rebuilt over the summer, maybe throw a rip saw track on for next year and double check everything this summer to make sure there is nothing else that it needs. If all goes as planed might even get it rebuild for a late Feb. trip and by next year it will basically be like a new sled.

Like I said above she is fast and able to keep up with the new ones with ease. Then maybe in a few years I can sell this one and my wife's and pick up two new ones.

So here is what I decide to put her back together with:

Doo Clinic Crankshaft with Fatty Bearings
2-SPI T-Moly Pistons or maybe Wiseco
Winderosa full gasket kit

One Question I do have is I was told here and by the guy I'm having put this together that the head is savable but it will have pits in it. If I understood him correctly. It's ok to have pits but high points are not. Should I look around for a head? Or will I be good with this one? Remember I want this engine built well, I do not want to see the inside of it again.

Does anyone have any suggestion on parts?
Or has anyone use any of the parts above?

 

[lofsfire]

Must be something in the water. 3 years ago my daughter blew up my 01 MXZ 600 on the straight away outside Boon. Still hauled it to Drummond the next weekend and put 350 miles on it on one cylinder, top steep 62 MPH. Coolant leak on the jack shaft blew a hole in the piston. Bored out and new pistons and 1500.00 later all is well, it is faster than ever!

All most forgot, Sorry to here that, I cant believe you were able to ride it the far! Any problems on the trip suck, just kinda puts a damper on the weekend.

 

[dab102999]

Yea from the pick that head looks good. Just take some sand paper and knock off the high stuff and it will be alright. And I know what you mean about that 700, It was and is a great motor. I always wondered why they didn't keep that and drop the 800 and perfect the 1000. I mean look at cat, F5's ran with the 600's; F7's ran with the 800's and so on. But I guess the manufaturers decided it would be best.
As far as a new sled, it all depends on your riding style. I was really washy at the start of the year on what I was going to by. I was riding a MXZ chassis just like you and the wife got a 07 Blizzard at the end of the year last year. I have a hard time on it being comfortable so I decided that I was going to go to the new XP chassis but was leary about the 1200. Still was on my way down to buy one when I found a really nice Attak that has had a alot of stuff done to it. I haven't rode a new 1200 XR but dang this Yammy is nice for sure. More then enough power for sure (out runs both of the 800 doo's I got) but If I was riding in large mogals all day hard I still think doo probably has that beat. As far as maintainace they all are expensive period. Just instead of buying oil all year you buy it in the spring. If you really went the cheap way I suppose you could change you oil for around $20 but I use synthetic so with oil and filter it is close to $40. Even though they say you can get a lot of miles out of the plugs I will change them at the same time. (since I have to pull so much off to change the oil) and that is close to $32 for the plugs. I supposed you wouldn't have to change them if you didn't want to. If you take it to a dealer to get it changed figure on about 2-3 hours for an oil change.
Rule of thumb 2 stroke is good for 3-5000 miles (what everyone else says and all of mine have always been 10-15000 miles before going away) and 4 stroke is good for 20,000 miles (so for me should be good for 100,000 miles right?!?!)