Cleaning out your crankcase

F

Frogster

New Member
Hey everyone. Everyone talks about which motor kit is superior. Imo theyre all pretty much the same, and the performance and longevity of your motor will be based on how you initially build it, and how you treat it afterwards. This is a flying horse motor from bike berry, and let me say they are not worth the extra money. Their customer service has been appalling, and the motor they sent me is pretty crappy. Im not at all impressed. It was clearly spray painted in china with all ports and spark plug holes open (Ive had to clean up the piston and cylinder wall with laquer paint thinner) and then wrapped in brown paper right afterwards as I have brown paper infused into the paintjob -_-.

Anyways, more to the point. Here is what I did. Not wanting to take the clutch and crankshaft fully apart to open up the crankcase. I decided I would just clean it out with fluid. What is in that cream cheese pot you may ask? Is it oil? No. Its wd-40 which is supposed to be clear. I filled the crankcase full of WD-40 as its a cheap lubricating cleaner i have around the house. I span the crankshaft around over and over to make sure the WD soaked and cleaned everywhere. When I poured it out back into my container, it looked like this. Although you can see it in the pic, there was a large amount of metal dust and fragments in there. I would strongly recommend you do something like this to try and flush out your crankcase when you first get your motor. After the first crankcase full of WD40 I filled it again with another WD bath, and this WD came out mostly clean. I then used some 5w20 4 stroke engine oil and filled the crankcase with this, moving the crankshaft around to make sure it cleaned everywhere. Then i dumped that back in to my container. Leaving my crankcase much cleaner and with a good film of oil over everything for when I first start it. Also, when I took the cylinder jug of my engine, I did not leave it open. I covered the open studs and piston with plastic sandwhich wrap and an elastic band. So im reasonably sure that the metal dust and dirt inside there was not from me, but infact from the factory.
K22WrA9.jpg
 
Assuming it is aluminum dust which is softer than the iron piston rings and the chrome cylinder plating, and the bearings.
How much damage could it cause?

I assume yours is not the only one, but not everyone washes out their crankcase.

Please note, I bought a carb and while changing jets I saw what looked like brass metal dust in the bowl.

May be good to rinse crankcases and spray out carbs with brake cleaner or carb cleaner before one assumes it is safe to install and use right off.
 
Let's not assume the crud you found was the fault of your vendor or the fact that the engine was made in China by mostly unskilled labor.

Back in my R/C model airplane days I used some rather high dollar 2 and 4 stroke engines. Some made in Germany, Sweden, Italy and Japan. The first thing I did when I got a new engine, in spite of how much I paid for it or where it was manufactured, was to disassemble it and put it in an ultrasonic cleaner with a solvent solution. You'd be amazed at what came out of some of those little gems; metal shaving and filings, dust, dirt and who knows what.
I never felt it was the hobby shop's fault or complained to them. They didn't build the engine, they just sold it to me. It was up to me to either run the engine as I recieved it or to assure myself that it was clean on the inside first.

Just my thought and opinion, for what they're worth.

Tom
 
2door said:
Let's not assume the crud you found was the fault of your vendor or the fact that the engine was made in China by mostly unskilled labor.

Back in my R/C model airplane days I used some rather high dollar 2 and 4 stroke engines. Some made in Germany, Sweden, Italy and Japan. The first thing I did when I got a new engine, in spite of how much I paid for it or where it was manufactured, was to disassemble it and put it in an ultrasonic cleaner with a solvent solution. You'd be amazed at what came out of some of those little gems; metal shaving and filings, dust, dirt and who knows what.
I never felt it was the hobby shop's fault or complained to them. They didn't build the engine, they just sold it to me. It was up to me to either run the engine as I recieved it or to assure myself that it was clean on the inside first.

Just my thought and opinion, for what they're worth.

Tom
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I pull the jug on every single new kit I buy, regardless of vendor.
I've found junk in several that would surely have eaten a main bearing or seal in short order if I'd run them without cleaning.
Not doing so is just asking for a grenade.
I have had no failures so far with any of my bikes during test running so I'm doing something right...I've done at least 15 so far.
I run all new bikes at least a tank before I list them for sale.
Once they sell, who knows?
 
Ya I hear what ur saying. Im using one of those nice ADA racing high flow airfilters, and an aftermarket copper fuel filter both from sickbikeparts.com as well as their upgraded gaskets. I also bought the the upgraded hardware, however im going to have to drill deeper holes to get the bolts to thread properly. I plan on designing this to be a higher perfromance ht engine, however I want it to last so im trying to do everything i can to be nice to it from the get go so it will be nice to me.
 
drilling doesn't sound right - wouldn't a couple extra washers do?

never bought h/w there so don't know if those bolts are oversized, but some areas of the case are a bit thin - I'd want to ask about that & maybe measure an old set of cases to check how much room there is
 
I'm assuming since all my motors were fine after cleaning that it was debris left from assembly in the factory.
 
maniac57 said:
I'm assuming since all my motors were fine after cleaning that it was debris left from assembly in the factory.
Click to expand...

yes thats what im assuming to. I dont care how it got there are what exactly it was (looked like a mixture of metal dust and dirt thats common in the job shop im doing my co op at)/ All I care about is its clean now and Im happy and I thought I should share this experience with everyone whos doing a new build
 
crassius said:
drilling doesn't sound right - wouldn't a couple extra washers do?

never bought h/w there so don't know if those bolts are oversized, but some areas of the case are a bit thin - I'd want to ask about that & maybe measure an old set of cases to check how much room there is
Click to expand...

they arent over size bolts. What they are is hardened, stainless steel allen key bolts and stud rods that replace the crappy easy to strip stuff. The only problem is some of the holes are just a tad narrow to fit the slightly wider allen key head (most of them fit just fine) Its just a 3 on the clutch cover and two of the engine case ones that i need to widen out the hole for the head so they will seat in there properly. They are really a quality improvment and im happy i added them into my last order with SBP. Those guys have always sold me quality stuff and been there to answer my questions.

http://www.sickbikeparts.com/catalo...ducts_id=43&osCsid=nip1rbvfqq1o8ufni8t128eik6
 
makes sense, but in that case I believe I'd be more comfortable with trimming the head size down a bit rather than enlarging the hole
 
crassius said:
makes sense, but in that case I believe I'd be more comfortable with trimming the head size down a bit rather than enlarging the hole
Click to expand...
I concure. You can chuck the bolts into a drill motor and run the head against a grinding wheel or belt sander to reduce the head diameter so they will fit the engine counterbored holes. Since you're using stainless steel you can even polish the heads using the same method.

I'd be very cautious about trying to enlarge the holes in the engine case or the side covers. There isn't much material there to play with, especially the cast covers.

Tom
 
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lol I got it done today with a my 20 dollar dremel :) Dw guys it worked out fine, didnt take of to much material just drilled the holes a few mm deeper and widened the out. Keep in mind I dont have a shop. My garage is filled to the ying yangs with old stuff from 18 years of my family living here, and my back porch had a nice uninviting layer of snow on it. Soo I busted out the power tools and the vaccum cleaner and worked on installing all of the new hardware and my noise deadening material things for inside the 3 covers, while my buddy worked on getting the sprocket aligned and then the back wheel back in to alignment with the bike. It was a productive day :P
 
No, I did that after the WD40. Put in the engine oil for the third bath. The purpose of the 2 WD40 baths was not to give the engine long term lubrication but simply to put a lubricating liquid that flows like water down in there and get it around so that when I dumped it back out, it would bring all the particulate crap out with it. I did the 3rd bath with oil so that I would remove most of the wd 40 and wouldnt be starting my engine for the first time using wd40 instead of an actual oil.
 
well I would've use mineral spirits WD 40 has abrasives in it which is hard on the chrome bearings and it also dissolves seals plastic and rubber especially not the derailers .call any bicycle shop will tell you that is a no no !!!
 
I used it in the crankcase briefly then washed it out with the thicker oil. I didnt use it on the bike. The engines running great
 
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