Wiseco piston failure after rebuild

[Turbo Johansen]

Hey.

I just rebuilt my patriot 850 because of failure on wössner pistons and installed wiseco. Had plenty of oil and premixed 50:1 also. Heatcycled the engine a few times after bleeding cooling system and took ut out for a small ride and the engine seized after 2minutes. Any ideas what happened? The cylinder is fine so is the other piston. I have verified oil pump by running it on power and it dumps oil in the case then. Picture of wiseco and wössner added.

 

[Turbo Johansen]

Forgot to mention rings were gapped to 0.55mm

 

[JMCX]

The same side failed? Did the OEM piston fail as well? The Wossner looks like lack of lube. How long did it last? The Wiseco looks like it got tight in just the one spot. Look the cylinder over close.

 

[gtwitch]

I would go looking at the PTO side main bearings and crank seal, Have any doubts, Call Indy Specialties and ask about the problems people are finding with the PTO side main bearing and the seal, they will enlighten you. Just saying because I have had those problems and pistons look the same as yours, also Indy says to use only OEM pistons if you can get them ( INDY can get them to you!!!)
gtwitch in wyoming

 

[Turbo Johansen]

The same side failed? Did the OEM piston fail as well? The Wossner looks like lack of lube. How long did it last? The Wiseco looks like it got tight in just the one spot. Look the cylinder over close.

The OEM pistons failed due to bad gas and detonation. But they handled alot of beating before they went. Wössners i think got cooked because of slushy coolant even when it was mixed 50/50 and measured good in a glykolmeter. But there was an extended period of very low temps when the sled was stored in a cold garage and that made the coolant slushy and the temps spiked to 70c rigth before the engine seized. I really hope its not an oil problem and its just bad luck with the coolant. I now mixed 60/40 and premixed 1:50 and never had more than 1/4 throttle on the wisecos. And after the heatcycles and an 15 minute warmup in a hot garage they lasted 2 minute ride on barely any throttle. Never went over 5000rpm on them but i didnt measure piston to wall clearence so im thinking its that, when i plugged the oilpump on 12v it dumped oil in the crankcase so i have verified its working, atleast when its connected directly to power, i have not measured while sled is running on the connector.

 

[HECKS]

Sh!tty deal.
Possible it cold seized ?
15 min warm up from a warm garage should have be enough to open up the thermostat and flowed coolant through the tunnel.
If not, the cylinders got a shot of cold coolant, once the t-stat opened while cruising around.
Spiking 70c before seizing, I would confirm your t-stat is working properly as well. Possible it was stuck closed and finally opened up and circulated the cold shot.

 

[Jay]

How many miles? Blown any belts? Checked runout on crank? Base gasket sealing? Any nicks or damage to crankcase surface? Like others have said I would look at the pto crank seal. Sounds like an air leak to me.

 

[Turbo Johansen]

How many miles? Blown any belts? Checked runout on crank? Base gasket sealing? Any nicks or damage to crankcase surface? Like others have said I would look at the pto crank seal. Sounds like an air leak to me.

I have actually not blown a single belt, i have been running indy specialty clutching and its running perfect.
No visible damage to crankcase. The gasket was new and no visible damage to that either.

 

[Jay]

I have seen where blowing a belt tweeks the crank. I have seen where a badly out of spec crank at rpm actually "ovals" the crank seal and allows air to leak past it. If you have checked your piston to cylinder clearance and it's good and your ring end gap is good then I suspect an air leak. Have you had the reed cage off? possible leak there.

 

[slash]

Check your oil pump gear Tatersporting has sean gear failures

 

[slash]

What caused the original set to fail ? did you fix the problem or toss new pistons in it and pray?

 

[whoisthatguy]

Is there an oil injection tube that could get plugged up somewhere?