Mighty Quinn

Well , It's been a while since I've been here & a while since I've touched my sled.I decided to tackle the motor that I puchased over a year ago & unwrap the crate it came on.Covered in dust,I unvealed the triple beast & set it on the bench.
I bought this thing for $700.00 complete carbs ,coils pull cord ,minuse the clutch.I was told it had 120lbs. in all three cylinders ,so I had to check it for my sake.I pulled the exsaust manifold to check the condition of the pistons,seems fine ,no scoring & the cylinders look ok from peeking through the ex. ports. Next I pulled the plugs & did a compression test.Pulled over 5 times heres what I got .120 mag, 118 cent.& 90 pto. So I decided to squirt some soap & water on the pto seal & then crank it over again , air bubbles started to apear after the first pull & increased in size after a few more pullsOK... that was disapointing & so were the compression #'s . Man I just don't have any luck what so ever.

My question now is ,with the seal leaking will that lower my compression #which is at 90lbs. I would appricate your comments & advice.Thanks guys .

white lightning

No .. however the seal leaks prolly indicated why the PTO side cylinder to go bad. You MAY not be in a bad luck of a thing, depending on how many miles the sled has - if it doesnt really have a high miles, you may get away with just replacing all the rings in all 3 pistons and change the crank seals on both ends (PTO / MAG side) If youre going to keep it, I would go for a complete top-end rebuild, with all new pistons/rings and crank seals - that depends on how far are you willing to go with your wallet and a risk youre willing to take. Anyone? WL

Mighty Quinn

Thanks WL for your reply , I should maybe mention ,since it's been 2 yrs. since I purchased the sled & never even drove it . It had problems off the start ,3 scored pistons on the origanl motor after taking a compression test the #'s were in the 90 to 110 range on the origanl. So I decided to find another moter well this one came up, (trusting the guy ...stupid me!) ,& now finding this out before I dropped it in the sled a year later .Can't get my money back now!
I was hoping to have some good news , but seems like mine is all bad. Nikacil cylinders at $330.00 a crack with tax , plus the piston & rings & gasket set your over $1500.00 in CANADA .
Tear this one apart & see where I stand... I guess?

Mighty Quinn

I'm really thinking someone did a poor job on either a top end rebuild & the rings didn't seat properlly,or,& so if I add a teaspoon of oil to each cylinder my compression #'s should rise ... right?,or not really?I'm courious on these reed induction triples?

white lightning

How bad is the cylinders on both engines? If somehow you can find out .. all you need is 3 good cylinders and if the pistons are good enough to reuse, all you can do is get a set of new rings, crank seals and put it in good case. If all else fails to go to that route, another thing you can do is part them out and sell them to others that are in need of parts - get as much as you can for it and buy another engine OR save to buy another sled that actually runs. WL

BC_Dan

Your cylinders can be repaired, Millenium Technology or US Chrome will repair and replate for about half what a new cylinder costs.

You definitely need the seal, if it's bad, it will lean out that cylinder and cause damage. That's likely what has happened to the compression. You won't know until you have it apart.

__________________
2007 Dragon RMK 700 155", 2008 RMK 600 155", 2006 RMK 600 144", 95 Prowler 550 2-up, 1990 Indy 650, Really OLD AC Cheetah

http://www.avalanche.org/accidents.php

Mighty Quinn

This price is an exchange price on 1 cyl. So... have to tear in the triple & find out more details why it's producing the compression #s it is ? S**ty but, seems like no other alternitive

Mighty Quinn

In looking at the pto. cylinder the cross hatching marks are pretty much gone, making the nicisil very shiny(chrome like).Looking at the other 2 they still have the cross hatching markes from honing ,& the top of the pistons on the other 2 are stamped STD. stating (standard), the pto cylinder on the other hand looks like it is stamped 890 ? Did someone do a cylinder & piston swap for that one cylinder?

I have been doing some reserch on the honing of nicisil coated cylinders & so far it seems like a (3M green scotchbrite pad) is the safest from a 28 deg.to 45 deg. angle in the cross hatching marks for retaning oil & compresson.Next is a FLEX HONE (ball type) slightly bigger than the cylinder hole itself.I'm questioning the FLEX HONE for ported cylinders in the avent it might chip the nicisil along the ports?

In conclusion,I wonder if the PTO cyl. is wore to much after the cross hatching is gone . I will be picking up a micrometer this weekend (for checking service wear max limit,out of round ,& taper.), & should I pick up a FLEX HONE (aluminum oxcide 240 grit)?
Sorry for the speech,Thanks.

Mighty Quinn

Hi guys,
In my adventures of tearing the top end down ,I noticed
PTO: piston std. stamp on top,bottom ring stuck ,slite blowby under bottom ring.Cylinder origanal cross hatch marks.90lbs.

CEN: piston stamped std. coated piston on sides (different piston?)slite blowby under bottom ring,rings not stuck . Cylinder origanal cross hatching marks.118lbs.

MAG: piston stamped 89D ? no blowby under bottom ring,no stuck rings .Cylinder is glazy ,hardly any hatch marks left ,slite more piston movement than other two when wiggled in cylinder?120lbs.

PTO seal with closer inspection was damage during shipping ? Dented seal,causing seal leak.
Still waiting on shipping of my FLEX HONE .

Any comments would greatly be appriciated.Thanks

ppolaris1010

sounds like you got a real winner with that motor.with all the mismatch parts makes you wonder what the crank looks like.if it were me and you dont want to dump a ton of money into it i would put new rings on the pto and new crank seal and run it.the other 2 cylinders are fine.

BC_Dan

One scenario is that the bad seal was leaning out that cylinder, which caused overheating and a collapse in the ring groove in the piston. That could also lead to overheating and premature wear on the cylinder sides. Usually, a lean condition will end up heating up the cylinder to the point that a hole melts in the top of the piston.

Examine and measure the ring grooves in the piston before you re-use it. You may be able to get by with a new piston/rings and use the old cylinder with a bit of work. Nikasil is tough stuff, it's hard to make any marks in it unless you have a diamond hone. I would be concerned about breaking the edges of the ports...

__________________
2007 Dragon RMK 700 155", 2008 RMK 600 155", 2006 RMK 600 144", 95 Prowler 550 2-up, 1990 Indy 650, Really OLD AC Cheetah

http://www.avalanche.org/accidents.php

Mighty Quinn

Yup...the mismatching of pistons in there are my head scratcher,even if a guy wanted to put new rings ,you don't even know what kind of pistons they are ? Polaris OEM, Kipex, SPI, SPX'or even a Wisco? Just seems wierd with the mismachting that's for sure!

Mighty Quinn

Yup...the mismatching of pistons in there are my head scratcher,even if a guy wanted to put new rings ,you don't even know what kind of pistons they are ? Polaris OEM, Kipex, SPI, SPX'or even a Wisco? Just seems wierd with the mismachting that's for sure!

Mighty Quinn

The dent in the pto seal looks like the owner before me tryed using a prying tool of some kind in the helping of getting the clutch off maybe, or it was in the event of it being shipped? There was no clutch with the purchase of this motor.There is no signs of the piston being leaned out,it is not scored or damaged just the stuck bottom ring.
The FLEX HONE tool that I purchased is a 67mm. 320 grit aluminum oxcide (ball) hone designed for nikacil ported cylinders ,slightly larger than the bore (66.6) . The company that I purchased it from specailizes in industrial machining equipment & advised me that they never had a problem with there other customers in the powersport industry of damaging the ports ,or chipping the nikasil.
With the mismatching of pistons how would you know which new rings to purchase?When you don't even know what kind of pistons they are ? I'm really leaning on the idea of all new matching WISECO ,or SPI top end for peace of mind ? Sombeach ... this is giving me a headache!

white lightning

For safe insurance .. I would get all new 3 set of pistons / rings. That way theres no mix and match. SPI is usually the cheapest to buy and I have had it in my '00 XCR8 that my buddy now owns. My other buddy also has it in his MachZ and in between both sleds, both seem to run good. I would also change the seals on both ends. When you do the job done right .. you should have a good strong running motor for years to come. WL

Mighty Quinn

I'll have to agree with you on that 100% there (White Lightning).These three different piston thing is just not right for me.I've been looking into a few differnt kits avalable for the top end & here are some choices,

OEM- 3 pistons ,rings ,pins & c-clips $119.00 plus shipping $30.00 = $149.00. (on line)



SPI- same as above for $139.00 plus shipping =169.00(on line)

SPX- same as above for $240.00 plus tax =$260.00 (in CANADA)

Wiseco-same as above ,also incudes top end gaskets from $325.00 (on line )all the way up to $530.00 (here in CANADA)

Mighty Quinn

Well... I did purchase the OEM kit for $119.00 plus shipping witch came to $151.00 so bite the bullet & see. Pulled the oringinal motor out today ,& got my FLEX HONE tool also .I'll be ripping the original motor down towmorw,top end of corse ,& see what I have from that moter .
Well like they say towmorow is another day ,& I hope it's a good one!

Mighty Quinn

Well in the event of tearing down the origianl motor I found a few things.First was the PTO side-
1-The piston had something dancing around on top of the crown of the piston,which marked up the head also.Noticed top ring groove where ring pin & end of rings meet togther was missing & broke a 1/8"in. off the ring & also gouged the cylinder on intake side.Scored also on exsaust side piston only.That cylinder was 90lbs, compresson before tear down.

2-Center piston scored on exaust side & little scoring on intake side.That cylinder was around 105lbs.compression before tear down.

3-Mag side same as center .That cylinder was about 110lbs.

Drained the oil out of water pump reservior ,which was very little took it off the block & noticed the plastic gear was stripped all the way round.Which in dought probably found a spot on the gear which it could'nt turn anymore & presto. You have three scored pistons from over heating.

Do any of you guys remember which acid takes off aliuminum off the cylinder walls (Mueratic or sulfuric acid) ?Can't quite remember.

RJ Gleason

Mueratic

__________________
Old Cat Rider
'93 Wildcat 700EFI
w/ Comet 108 Pro-4 clutch & 01 ZR skid

'90 Wildcat Project in progress.

Vintage (sorta)
1980 Indy Trail 440 (for sale)
1980 AC Pantera (donor engine to the 90 wildcat)


http://www.dcdrifters.net/


Senior Warden; F&AM Dryden Lodge# 472
http://www.masonicdryden472.org/

Rules of this forum are strictly enforced!

Mighty Quinn

OK.... thanks RJ ,but I did try the muratic acid on a Qtip rubbed it on a spot ,& then wiped it off ,not much happend .I'm I doing something wrong like wait for a time period ,or something else?