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I'm looking for a good rod as a core.

Casting #1554530 with a total weight of around 843g for #6.

At some point #6 was replaced and it weighs 20g less than its buddies. I'm looking for something closer in weight before we start balancing.

ashyers wrote:I'm looking for a good rod as a core.

Casting #1554530 with a total weight of around 843g for #6.

At some point #6 was replaced and it weighs 20g less than its buddies. I'm looking for something closer in weight before we start balancing.

Andy, that weight must include the piston pin bushing, and the bolts and lock nuts (those late rods probably don''t have the counterbore for the lock washers)?

I have quite a few 1554530 rods on hand, but they're all without the bushing. If you can press out the bushing and PM me the weight, I can probably find one that's close.

Elwood,
You're correct, it's rod/cap/bushing/nuts. It's a newer rod w/o washers.

We can press out the bushings tomorrow. Do you have any suggestions for removal? I'm thinking propane torch, penetrating oil, and a few tons of pressure. I guess I'll have to make the driver tonight.

Thanks for the help!

I'm working on finding a head gasket that fits well now. I may have one made if it's not too costly. I'd like to minimize the amount of machining on the block and head. I want to keep the transfer area in the head and the valve seats in the deck.

Andy

ashyers wrote:Elwood,
You're correct, it's rod/cap/bushing/nuts. It's a newer rod w/o washers.

We can press out the bushings tomorrow. Do you have any suggestions for removal? I'm thinking propane torch, penetrating oil, and a few tons of pressure. I guess I'll have to make the driver tonight.

Thanks for the help!

I'm working on finding a head gasket that fits well now. I may have one made if it's not too costly. I'd like to minimize the amount of machining on the block and head. I want to keep the transfer area in the head and the valve seats in the deck.

Andy

The rod bushings press out very easily. You won't need heat or penetrating oil. If you have a bushing driver set, like a Snap On A157C, it will be one of the common driver sizes to press it out, but I can't recall off hand which size. Shouldn't require much force. Even a hand arbor press should be able to o it.

Elwood,
They did come out easy. That's a nice change . Made up a driver and a few raps and out it came. I didn't realize it was a split bushing until it was out.

I borrowed Hilde's yarn scale and the bushing is 11g. I'm told the yarn scale is reasonably accurate, why you weigh yarn I have no idea, but any scale in a storm.

Andy

Some of the piston bushings that I've removed have been split, some solid. Personally, I prefer the solid, and would not install a split one, but I can't say that the split ones I've removed look any worse for wear than the solid ones.

So you need a replacement rod close to 832 grams, including cap, bolts and nuts. I'll check my stock and let you know what I have.

Elwood,
Thanks for taking a look. I have my fingers crossed!

Andy

Andy, my conn rod spreadsheet shows that I have one 1554530 rod that measures 832.1 grams (small end 259.5, big end 571.3), but I want to visually inspect it first to make sure that it's in usable condition.

Do you have a tool (Sunnen TN-111 or similar) to inspect for twist? Are you going to crack check the rods (either magnetic or surface dye penetrant testing) before you finish them?

Elwood,
I don't have the tools to rework the rods, going to have to send 'em out. We're going to install new bushings, balance them and then they will go out to get shot peened and sized.

The cam's on the way back, the block is nearly ready to go out and I may get a chance to drop off the crank this week. This stuff always takes longer than expected!

Looks like we're going .020" over on the block and the rod journals will likely go .020" under.
We still need to check the mains.

Andy

ashyers wrote:Elwood,
Thanks for taking a look. I have my fingers crossed!

Andy

Andy, email sent with photos of the rod.

Elwood,
Email received and returned. Thanks for the help!

Andy

The parts are rolling in! Have the valve guides, rod bushings, replacement rod (thanks Elwood!), camshaft, tappets, head gasket and cam bearings in hand. We should see the pistons, oil pump, springs, valves and rings this week.

Finding a head gasket that fit took a little work, but that's sorted now too. At this point it looks like we're going to "0" deck the block and mill the head to obtain 80cc's. The valve job is currently a single angle, 45deg, that's it. We'll fix that and may do a bit of work on the back side of the valves too.

I have a few stock intakes I've picked up and the amount of casting error in the flange area is impressive. One of the military ones has a 1/8th step where the ID of the manifold meets up with the flange that bolts to the block. The civilian one is the "best" with reasonably smooth contours. Hmmmm...

Hope to get some of the bits to the machine shop this week. Next week it's Spring Break and the kids are off and we're headed to Petaluma for the MVCC Spring Meet . It would be nice to have something to play with after the break.

Andy

Things are moving, at a glacial pace, but moving. Between vendors not sending the correct parts, machine shops not hitting deadlines, and all the usual end of the school year shenanigans I'm not sure we're going to hit the dyno by next week. Not having the cylinder head may ensure that... I recall "Sure, we can turn that around in a day." Seems my recollection may be unclear, or we're operating on different clocks, that was a week ago.
The assembly has gone OK. No major issues and I think this lump will work well. We've made some minor changes and I'm very curious to see if they have any effect on the dyno. I was really excited to get this thing up and running, but now it's become a big push just to get it assembled. I may have to bribe the kids with some BBQ to wrap things up. They seem to enjoy coming down to the Shop on a Saturday to do some work if I feed 'em. I knew that free gas grill we fixed up was a good idea!

It's getting closer, but not close enough .

We've been waiting on the cylinder head for a 2 weeks... Maybe it will get buttoned up tomorrow, but running on the dyno by Thursday (last day of school) seems unlikely. I need to speak to my students and see how badly they want to finish it. If they're game we could have it running next weekend. If the head's done!!!!!!!!!!!! AHHHHHHH!!!!!!

I've never waited 24 hours on a flattie head. Did they ruin it and are trying to replace it with another?