First Post!!! 99 Challenger 1800

[Pollo432]

Good info! Thanks guys. Tomorrow I will pull plugs, remove plastic guards and see if she’ll turn!

 

[Pollo432]

Ok left engine turns freely and it sounds like it’s making compression, right engine won’t turn. Ill check compression on left side before I do anything. Tomorrow I’ll buy a new battery to check electrical. Best place to buy rotating assemblies? Also why does everyone replace entires rotating assembly instead of just rods pistons and bearings? You save a big chunk reusing the crank. If it’s in good shape run it right?

 

[Ankeneyou]

Typically not on these 2 strokes. You will have to pull the entire engine apart and inspect the crank to ensure there is no rust and that everything is smooth and within tolerance.

You also have to worry about the crank seals as the 2 inner seals which seal the rotary valve cavity tend to leak over time. This causes oil to fill the cylinders while sitting and can cause you to replace the crank in an otherwise good running engine.

I'm guessing by looking at the pics both engines had water in them and will have rust on the crank bearings as well as counter balance shaft bearings. Any rust and they like to blow nice big holes through the sides of the cases.

 

[Pollo432]

Thanks for the info, any info on rotating assemblies? I see WSM on eBay. Any sponsors that have better pricing?

 

[mikidymac]

These are not like a car crank, you can't just install new rods and bearings and be done with it. They are pressed together so you need a really big press then you have to make sure everything is pressed together exactly then have the proper tools and experience to make sure it is true and not twisted.

It isn't realistic for someone to rebuild a seadoo crank at home. That is why you just buy a complete crank from SBT or WSM. PWC Muscle here on the site sells WSM and offers forum discounts.

 

[Pollo432]

Update! It’s been a while, been busy. Got to working on the boat, both engines are turning. Put a battery in and both engines crank over smooth. Tomorrow I will check compression.

 

[Pollo432]

These are the numbers I got. Engines turn over real smooth.

 

[Pollo432]

I am going to rebuild carbs, change out oil lines and replace filters.

 

[mikidymac]

Either your gauge reads a little high or you have oil in your engine. Perfect compression is 150 psi and a stock 787 will not be higher than that unless you are compressing a liquid.