Salt water marine engine rusty top end

[gazza2006au]

Hey guys so I bought another jetski looking to get it running and use it for wetting a line next summer when my mates boat is full no point taking my boat out solo

Old mate I bought it off swore the motor was not seized however we could not turn it over upon later inspection it was found to have injected salt water and was not flushed

Now the top end is a absolute mess no:1 no:2 cylinders both seized I actually had to press the piston out of cylinder 1

The little end bearings are rat poo totally rusted and seized

I tried removing the pistons with a long bolt it kept stripping the bolt I tried a make shift home made hydraulic press still no good these piston pins are stuck

What is the next step? I am trying to salvage the $1000 crankshaft

Unsure how to post pics I will do it when I jump on the laptop, jetski is a Yamaha XL1200 1999 3 seater

I think it may have been a fishing jetski because the water squirter on the back has been relocated maybe for a esky

[BM]

Gazza,

They are likely a Nikasil coated bore so cannot be re-bored and need to be re-sleeved. About $600 per cylinder. If the small ends are rusted then I would say the crank is rooted as at minimum the small end journals are water damaged and not able to be linished out. I just bought a crank for a 2 cyl 760cc waveblaster I am rebuilding which retails to the public at about $700. Not sure of your crank cost but I could find out. Its sounding like a lost cause Gazza but you do seem to get into a few of these type lost causes given your posts over the last say 8 years!!

[gazza2006au]

Financially it's not a lost cause BM the jetski cost only $500, a crank is $995 cylinders should only.need a hone the two busted cylinders i'm pretty sure are steel sleeve, I will need to add a top end kit about $500 and a further $200 on gaskets and seals

Cheapest one I could find on gumtree price was around $4000 but most go for around $4500

[BM]

Ok. At $500 it may be salvageable. I paid $500 for this Waveblaster 2 760cc. You need to check if they are Nikasil bores. This 760cc is and as such is not reboreable. Also the bearing that supports the jet shaft to crankshaft union can be an issue. Springvale Jet Wreck in Vic are very good on price for all parts and have been doing it for 30 years. Give Joe a call. I use him for all jet ski parts now. Best prices that I have found and a wealth of trade information.

[gazza2006au]

I should be able to double my money if i sell it, i had a Yamaha GP1200R Millenium Edition the grey and what model i had pulled the motor out and rebuilt it but decided i needed to sell one of the jetskis as i had two i also had a Seadoo GTX 1997 that i also done afull engine rebuild but the thing was the GPR was only a 2 seater i didn't like that i wanted a 3 seater for the fishing stability and the extra seat but the Seadoo GTX was a vintage model, so now i have this beast below I'm looking forward to some hooning to the location wetting a line and blasting back before storms hit

When i had the GPR Yamaha i read up about the driveshaft bearing and it cost a monster to get a new one for what it is hopefully mine is ok

I think i agree with you about my crankshaft i think its cactus but i need idea's on how to remove those seized piston pins as the crankshaft comes out between the two crankcase halfs

now for the glorious pictures

[gazza2006au]

BM there is a guy in Sydney called Greg Balls Engineering he does pressed cranks he even turns one piece crankshaft web and pins into rebuildable cranks pretty nifty shop i may see him before i fork out for a new 1k crankshaft as he may rebuild mine cheaper

[BM]

The Springvale guy is much the same.

[gazza2006au]

I have come to this conclusion, this motor has been hydro locked and now after spending countless hours i pulled out the big guns i was using the rattle gun to move the piston pins one pin on the front piston moved 1mm so its good to say these piston pins have been bent by the water ingestion

i have never encountered this problem ever and i have swamped a few jetskis with salt water

the difficult part now is surgery on both pistons i need to delicately cut the pistons away from the conrod without nicking the conrods :o i will take pictures as i progress currently looking into a Dremel to use to cut the piston away

[gazza2006au]

Some pictures of the cylinders, 2 cylinders have steel liners or sleeve the 3rd is brand new and a nicosil cylinder (3rd cylinder no shown)

these cylinders were pretty rusty but cleaned up with a tickle from the hone than a clean followed by a generous lube of 2 stroke oil

i will be picking up a 6 ton hydraulic press this afternoon for the piston removal i decided not to cut the pistons that was a drastic decision however i could just chop the two conrods in half since those rods will be getting replaced 3rd rod depending on what it looks like when the crank is pressed apart (need to remove the pistons so the crankshaft will drop out of the top casing)

[gazza2006au]

Here is what the cylinders look like now cleaned up, As for the removal of those pistons anyone that has lifted a 3 cylinder motor will know they are not light so i will need to hang the motor on my engine hoist balancing while the piston is in the shop press should be fun..

[stevej]

your not going to use those bores like that are you ?

[myusernam]

Sounds like you paid $600 too much!

[gazza2006au]

your not going to use those bores like that are you ?

steve nothing wrong with the cylinders they are up to spec the only way of getting rid of the colouring is to rebore but that is nothing the rings will wipe that clean in no time once i get her running, these cylinders were rebored .25mm over, 5 hours ago doing another rebore now is not required the rings will seal well once they are run in

[stevej]

ok guess cant judge it off photos

I was under the impression bombardier/rotax and Yamaha nikasil the bores though
but if someones done a rebuild already they dodgied it and dint recoat

[gazza2006au]

Yeah at one stage the jetski had a complete overhaul what happen at the time was the owner had all 3 nikasil cylinders bored and steel replacement sleeves installed in place of the nikasil bores, I have 1 nikasil and 2 steel cylinders the last owner that just done the top end rebuild and bodged it bought a brand new cylinder the old one must have been destroyed beyond repair hence the new one, I think the steel cylinders were chosen in favour over the oem cylinders because u can get the steel sleeves bored out over and over cheaply for around $50 each where as a nikasil cylinder repair cost $500+

[gazza2006au]

The 6 ton shop press i picked up was way smaller than i thought it would not fit around my motor to press out the piston pins, only one way forward and that is to cut the conrods in half, i got the motor out and sat it up vertically around 3-3.5 litres of rusty salt water poured out of the bottom end with a little oil

this is looking like a complete new crankshaft and a complete new top end, the reed cages may need a soak in some sort of rust remover than lubed or depending how bad they are a new replacement because they are meant to be coated to stop them rusting than rusting out other parts like the rods and bearings

i guess this happens when you hydro lock an engine with salt water, if the last owner who was mechanically inclined had pulled the head gasket off and cranked her over with spark plugs out than flushed the crankcase the day it happened this would have been a different story

i will grab some pictures of the two different nikasil and steel sleeve cylinders when i get a chance to show the different so people know what we were previously talking about

[gazza2006au]

Heres the pics showing the difference between aluminium cylinder with nikasil coated sleeve and a aluminium cylinder with a steel insert sleeve

[gazza2006au]

Got that crankshaft out check out the video below https://www.youtube.com/watch?v=zqbuhGBBg3k&t=3s