Scored piston/failed oil pump on 2008 Roughhouse

jayseye · Post by **jayseye** » Wed Aug 26, 2015 2:21 pm

I've just become the owner of a used 2008 Genuine Roughhouse and for the first week it was running great, but now I've run into some trouble.

Could be a coincidence, but immediately after a VERY heavy rain I could not get it to start again.

I had power, checked for spark, and there was gas in the tank, so I ended up having to take it to the shop. Now, don't quote me on this as I'm going off of memory from our phone conversation, but he says one of the pistons looks really scored and he believes this happened because the oil pump failed.

This is NOT a stock roughhouse. It has a big bore kit, prima exhaust, cold air intake, carb has been rejetted, and it has been geared to "go faster" and a few other little upgrades like battery, spark plug, etc.

So, now the questions!

The mechanic wants to replace the piston/ring, and I guess for the kit that is on there he says it might be expensive, has anyone dealt with this before to know sort of what cost I should be looking at?

He didn't mention replacing the oil pump, just said that I should start premixing the gasoline. I was under the impression that the oil pump variably put in oil depending on throttle, so is premixing going to be fine? Is there a way to see if the oil pump is actually not working, and if so should it DEFINITELY be replaced?

I apologize if some things I said don't make sense, I am just starting to get familiar with these engines as this is my first scooter. Thanks in advance for any help!

avescoots1134 · Post by **avescoots1134** » Thu Aug 27, 2015 8:15 pm

If it has a "cold air" intake (likely a pod filter), you most likely ingested water into the engine during the rain. The oil pumps pretty much never fail, some people mistake them as failed if they get ran out of oil and don't pump when refilled. In this case you have to bleed the air pocket out of the pump.

EDIT: If your mechanic doesn't know this, you should likely take it somewhere else.

jayseye · Post by **jayseye** » Fri Aug 28, 2015 7:21 pm

Here are some pics he sent me.

http://i.imgur.com/EdnhPRF.jpg

http://i.imgur.com/z6WWzgD.jpg

Has anyone seen this before? Ended up replacing the whole cylinder kit which he charged me $300 for.

avescoots1134 · Post by **avescoots1134** » Sat Aug 29, 2015 2:26 am

Looks like it's either jetted wrong or you ran it too hard for too long. Either way, it got too hot. Performance parts sometimes have more of a tendency to go boom.

jayseye · Post by **jayseye** » Mon Aug 31, 2015 9:18 pm

avescoots1134 wrote:Looks like it's either jetted wrong or you ran it too hard for too long. Either way, it got too hot. Performance parts sometimes have more of a tendency to go boom.

Thanks for your help!

How would I be able to tell if it was jetted incorrectly? If I rode it too hard is it strange that I did not notice anything wrong when riding the scooter? I admittedly don't know very much about this, but it seems like I would have noticed damage like this occurring while the scooter was running wouldn't I?

babblefish · Post by **babblefish** » Thu Sep 17, 2015 7:35 pm

In addition to what avescoots said, foam pod filters don't do much to stop water because, after all, they're just foam. Also, in case you don't know, they also won't stop fine dirt particules if they're not reoiled after they are cleaned. Some people just use WD40, but I prefer airfilter specific oil because it's stickier so dirt, well, sticks better plus less of the oil will get pulled into the engine. That being said, don't soak the filter, apply just enough to coat the foam then squeeze out the excess on a paper towel.

You can check if your engine is running rich or lean by taking a sparkplug reading. If you don't know how to do this, Goggle "How to read sparkplugs" and/or go to YouTube and do the same. To be safe, for a 2-stroke engine, I like the plug to be a little darker than what is suggested as perfect. A little more lubrication couldn't hurt, especially if riding in hot weather, carrying a heavy load, or there are a lot of hills.

From the looks of the pictures of your piston/barrel, I'd say your mixture is pretty close, but check it anyway. It looks to me like the rain washed whatever dirt that was trapped in the filter into the engine thereby causing the scoring seen. Just a guess of course. I ride year round, so I elected to not use a pod type foam filter and just modify the stock airfilter box for more flow instead. It actually works quite well.

lovemysan · Post by **lovemysan** » Fri Sep 18, 2015 1:43 pm

My 2 cents: It wasn't water ingestion at all. The damage looks like it seized from getting too hot. What caused this could be lean jetting or an undersized carb. An undersized carb will cause elevated engine temps. I've also found that pod filters are much more temperature sensitive i e meaning the jetting will change. My kitted roughhouse I drilled the airbox with 7 1/4" holes and cover them with tape as temps get under the 70f range. Colder temps equal leaner jetting. Also my personal experience has been performance parts equal frequent repairs. My stock roughhouse went 7000 Miles with just a prima pipe and broke a piston circlip trashing the top end. The wrist pin bearing was getting pretty tired as well. I feel it was Rpms that killed it. Currently has a malossi 70cc kit on it that soft seized after about 500 miles of riding. We tried to ride a little to fast for too long. Imo I would budget $300-400 for repair every 5000 miles. I would keep all extended cruising under 45 mph(stock gearing).

agrogod · Post by **agrogod** » Sun Sep 27, 2015 8:32 pm

To add on to the above conversation I had to rebuild my top end for a whopping $124 price tag. If you do the work yourself you can save some big dollars. And you can always return the engine to stock by using stock parts, it doesn't have to be BBK.

SlickRick · Post by **SlickRick** » Wed Oct 07, 2015 1:30 am

I agree with it looks like a hot seizure. You should alwayse add 1Oz of 2 stroke to your gas when running a 70cc kit. Ask your mechanic what jet he's got in there he should be able to tell you a specific number right off the cusp