Re: The 2010 FrankenMerc Project
O.K. lets talk wrist pin circlips. The ones that came with the pistons had me scared so I ordered a set of Merc clips. Those arrived today and I changed them. I'm sure glad I did because a couple of the came out way too easy. The Merc clips set in perfectly and are tight like they're supposed to be.
It's another one of those situations where if it doesn't feel right, do it again until it does.
I then assembled the crank. I did not lap the sealing rings like some of the race motor builders do. I just don't see it as being necessary or even helpful. There is too much slop in the grooves and the grooves aren't perfect enough for me to say the lapping is going to reduce wear. It's not done to improve sealy by the way.
Here's the assembled crank.. Note that the oil gear is on the crank. Taking it out on the 7 ring cranks would leave a large hole in #2 and filling it in would restrict oiling to the center main so you must put it back on. Remember to use Loctite 271 (red) on the screws.
The crank was first washed in warm soapy water with the lower main already installed. Then is was blown dry with compressed air and immeditatley oiled with 2 stroke oil. The bearings were aslo drenched in two stroke oil.
The crank is then laid into place in the block and the center main bearings adjusted so that the fall onto the pins in the block. The sealing rings are turned so the openings are all facing up. These will be centered up after the rods are fitted to the crank.
The upper and lower bearing caps are slid into place without the O rings and held loosely with the bolts. This is the fitting stage. Once the rods are bolted on we'll pull the end caps and check the fit of the front half.
The reason you don't put the O rings on now is because you can pinch them during the fitting process and they will leak.
Here's the upper bearing holder/cap -
Here's the lower -
I always put new seals in the bearing caps. It's just like change the bearing seals on your trailer wheels except you put a couple of drops of red 271 loctite on them. You need to buy these separately, they do not come in the gasket set. There are three, two in the lower and one in the upper and they are identical.
As you going to dyno this to see how much power it makes in the end?
