440 Intruder

[58Evinrude]

Another week, another try at starting it. I got a couple of coughs, maybe a 2 second spurt once, then nothing. Getting a bit frustrated with something that was supposed to be in running condition, so I yanked out the motor, and started pulling it apart. The timing mark was where it should be, that throws my idea of bad timing out the window. Lets split the case. The case has been apart fairly recently, not much dirt or grime on the motor at all. Bolt heads are all good, all feel evenly torqued when I cracked them. There's enough excess case sealant to seal up about 3 cases, it's hanging out all the way around the case. I'm wondering if the seals have been done??

Guess what, the mag side seal is not sealing anything!! It's split wide open, the spring is off, the rubber is wrapped around the crank maybe 1/2 way. The clutch side looks OK, from what I can see. But it's coming off too, I pull the oil pump gear, and inspect the seals.. they look OK, but they are getting replaced. So, now for a seal and gasket kit, and I'll let you know what happens next

I'm going to hold off on changing the rings on the mag piston.. I've got them, but I want to see what happens after the new seals are in. Will the compression come up to equal the clutch side 150 psi, or stay at 120? I'm really hoping it comes up!!

[Lloyd (ljm)]

  Crank seals won't raise the compression. It should run with new seals, but the compression will most likely stay the same

[58Evinrude]

I didn't think the seals would raise the compression. So now I'm wondering how to prep the cylinder walls for the new rings? A light sand maybe, with something like 220 or 400 grit? Or can chrome liners get a light hone? Or do I do nothing? The pistons both look great on the exhaust side, there are some marks on the intake side. I guess running it without an airbox or filter has let some stuff in to score the pistons.

Even if I don't swap the rings out, at 120 and 150 psi, it's higher than what I've got in my SRV (100 each side), and that runs not too bad.

[jimvw57]

Clean the surfaces whee the seal sits real good, and use a bit of sealer around the outside of the seals. Clean the crank were the seal sits too, and coat with grease on the crank, and pack the back side of the seals with grease. That will help protect the seals if the motor gets flooded, and the grease will lubricate the crank until the oil gets to it on dry startups.

I have had a few sleds that wouldn't start and it often is the crank seals, even when they were replaced.

Your compression may get better after you put a few miles on it, If the rings are run for awhile, they will wear to match the cylinder so see how it goes.

As I have said before, Crank seals, Crank seals, Crank seals.... welcome to the club!

[58Evinrude]

I don't think this sled was run much after it was torn down, and the drifter jugs put on. The tops of the pistons are pretty clean, so are the exhaust ports. Maybe the seal was bad, they didn't notice, and gave up on it when it wouldn't start or run. Maybe after I get it running with the seals replaced the rings will seat better. Or the seal could have torn after they got it together, and they gave up. Who knows, I'm not giving up on it!!!

[58Evinrude]

Got the seal and gasket kit today, I'll have it together and back in the sled on the weekend. Crossing my fingers it starts, and I get to take it for a run!!

[58Evinrude]

So I ran into a snag.. while I had the engine apart, I figured I'd change out the rings on the side with low compression. I found that the person who worked on this before, was not a mechanic!! After I pulled the jug off, I found the remains of a piston pin circlip sitting on top of the crank. They must have dropped it, and not bothered to go and get it!!

There were still 2 clips in the piston, so after they dropped one, they just installed another. Great!! You can see the damage it's done to the piston. The cylinder is damaged about 3/8" up from the center transfer port only, so it shouldn't really influence the compression. I sanded down the high spots left on the piston from the groove, and dropped the new rings on. I had to take a dremel to smooth down the inside of the wall around the groove in the cylinder. It's only about 1/4" square, right above the transfer port. It's not the right way to do this, but I just want to get it running this year while the snow is here. I'll try and find a new jug and piston later.

The 2nd pic is what the clip looks like after I fished it out

[jimvw57]

Ouch!! It is amazing what people do to these sleds. I found a crankcase that had a hole in it and was patched with JB Weld,and lots of mis-matched pistons/jugs, messed up carbs, all kinds of stuff. Hope it works for you. (I'd give it a try)

[58Evinrude]

So I have to ask, would people do this to their cars? No, but when the sleds quit running, it's the sleds fault!!! Idjits!! The motor is going back in the sled on Friday, and I hope to have some good results. I've still got lots of snow on the ground

[58Evinrude]

I just realized I haven't updated this recently. Sorry, got busy with stuff. Got the engine bolted back in, and it took some doing, but I got her running 
I need to find a non-econo jet carb, because mine isn't working right without an airbox. Other than that, it's running pretty good. Best top end is 55 mph on the lake, again that's because of the carb. The suspension was seized solid, and the seat was frozen, so it was a pretty rough first few rides.

The seat's been thawing for a week now, and should be pretty much drained of water. It's in my bathtub at the cottage.

For suspension, the front K arm is pretty rotten, and the shock is seized solid!! I did get some welding done to the frame, it, to brace it up, but I came up with a better idea instead of just re-building the original. I have a complete Yammi SRV skid in good shape, that I compared to the Kawi.. close fit!

I made a new rear pivot shaft, needed 'cause the Kawi tunnel is wider, and the Yammi axle is a bigger diameter. The front Kawi shaft will work, it's a bit smaller in dia. than the Yammi one, but it will work. The front axle is in the same position on both skids, I have to move the rear axle ahead a couple of inches.. some new 16 gauge tunnel supports will hold the new axle in position.

Hopefully, I should have the new skid in place on the weekend, and maybe a new carb for it too. Then I can feel how it rides when the suspension works, and the seat isn't a block of ice!!

[58Evinrude]

I have the carb in hand, it's a VM 34. I've got a 340 main jet installed, and it will be going in on the weekend, along with the new skid. We've got another 4 inches of fresh snow, and I'm hoping to see what the Intruder has in her now.

 

[58Evinrude]

The SRV skid is in, and it makes a big difference in ride quality and handling. And I got the new carb installed, and it woke the old girl up. It still needs some fine tuning for a good midrange response, but it idles and runs good wide open.Here's some pics of the Yamaha skid installed on the Intruder, and the last pic shows the new top speed I got out of her on Sunday. Previous best speed with the econo-jet carb was 56 mph.

I'm going out tomorrow and buying a 78 Intruder 440.. this one is complete, and has the Intruder jugs, twin carbs, and an airbox. I'm interested to see how it compares to the 80 with the Drifter jugs and single carb.....