Help! Mystery starting problem

[rkluck]

I may be wrong but it seems like something had to happen to it for wear like that with only 320 hours.

 

[KXCam22]

Andy,
From you pics the piston crown and head look very clean. I wonder it you have been getting a bit of water in there. I used to run a tuned turbo truck with water injection and the top end would be super clean like that

 

[Blazin14]

I have been following the progression of posts. I'm no engine expert, but I'm just too curios, so I've shared your photos with some fellow engineers at work, and the common thought was that theses marks could be normal wear on a used engine, but not directly from debris from the exhaust job. Also these engine heat up and cool down at much higher deltas than car engines, have you been using synthetic oil? We don't think those marks would cause such a low pressure reading that it would cause the engine not to start....

Like an early poster stated, does the temp sensor work? that engine could have been exposed to higher temp causing thermal growth....

I hope the best for you and great work so far. Please keep us posted

Yes the mystery continues...

 

[andyak]

@Blazin14 - I only put on around 20 minutes on the boat since I purchased it after I resurrected both engines from the dead (they had bad starters and had been sitting). I used synthetic, but who knows what prior owner did.

The cylinders were not that bad, dropped at machine shop - they will let me know if I can do .50mm or 1.0mm oversized bore.

If you look closely at the piston photo on the edge - you can really tell in person - the rings are so worn they do not stick out at all past piston wall - thus low compression.

 

[andyak]

@KXCam22 - Since I know not the history of the boat, except that it probably saw some hurricane action (rear windows gone, and some fiberglass work and complete repaint) - it could very well have been run with water in the oil... I DO know that the crankcase seems fine and no structural damage anywhere on block. I will replace all bearings, pistons, rings, rod bolts, nuts, gaskets, and rebuild the oil pump with some new parts. so hopefully it will be like new when done

 

[Big Shasta]

Hopefully you got it for a steal and this is just part of the rebuild process.

 

[andyak]

Yeah. Got the boat for less than 4k. But already put 6k of parts into her and the trailer

 

[KXCam22]

I was thinking more like possible water into the combustion chamber due to leaky head gasket. Cam.

 

[Big Shasta]

Yeah. Got the boat for less than 4k. But already put 6k of parts into her and the trailer

You're still way ahead. I'm glad to hear it.

 

[andyak]

Just got my bearings in. Have my plastigauge set - still need a piston - these are for the Jetski fx140 block- it will get done first so will be going in the boat.

Am I correct in my assumption that the rear gear units to coupler are the same (ratios same) for the fx140 ski and the 140 engine in our standard ar230 boats?

Also, the 2002 fx140 engine has an oil system with a separator box- is this desirable or should I use the 2005 ar230 oil tank and pump and nix the oil separator?

Any plastigauge tips?

Thanks
Andy

 

[andyak]

I am close to done on this rebuild!

Just waiting for oil pump rebuild kit - not taking chances on low oil pressure as I didn't know what caused wear on old pistons in other block.
This engine has 2002 FX140 fresh honed block with new plane and rod bearings, 3 used pistons and 1 new piston all oem standard with new rings.

Yes, you can just put in the pistons with the crank in the other half, and the piston half upright - But I had 1 set of hands and didn't know if rods and bolts could be lined up easily without scratching when putting in the crank after pistons - so there ya go.

Tip on cheap ring compressors - put flush on table after tightened around piston and tap any edges of doubled up sleeve so they are even and flush when you put up against cylinder block. I used wooden end of hammer that worked perfect for the final piston hit into block.

I decided to put this one together with new rebuilt SBT head, and exhaust from the jetski - I used copper spray gasket on the gaskets including the head gasket.

Plastigage shows at lower end of good (tight!) for all crank bearings, and at the upper end of good (even with new bearings) for the rods - good thing I ordered new bearings
I wish the green plastigage scale went a little tighter.

Should be in the boat by the weekend!

 

[andyak]

The other good news on the original block that had the worn pistons and visible vertical scratches.... the machine shop says it will be good to go with just a vigorous hone job- scratches were very very shallow. So I can use OEM standard pistons & rings - sweet!

Now if the other engine in the boat has any issues I will be ready to go with replacement.

 

[andyak]

Got the engine installed in the boat today (after 4x in and out I feel like a seasoned yamaha tech - haha!).

I put in 4.5 quarts of straight penzoil 10w-40 for the break in - I like that it is really light and I can see when it is time to dump and start synthetic.

Before cranking in the boat, I put a small amount of 2 stroke oil in each spark plug hole. Then I kept the gas pump disconnected, and cranked the engine - I could tell right away the increase in rpm when the oil was pumped into the block and through the bearings.

Then I hooked up the fuel pump and cranked again a couple times.

Finally, I installed spark plugs with a small amount of anti-seize. I put back the coils, wired it up, and turned the key......

















grumble.... grunt grunt

VaVOOM!

Running!

nice idle- a couple little revs and then shut her down. SUCCESS!!!!



OK - what is the preferred engine break in method?

Can I run her on the driveway? or should I drive to the lake to break in under load?

Thanks for all the help guys!

 

[buckbuck]

Congratulations. We appreciate your documenting the adventure. I am sure someone will be asking advice of your experience.

 

[MikeyL]

@andyak ... Ya DESERVE this one, Son !~ Well Done ! VERY well done !

 

[andyak]

take a listen...

 

[MikeyL]

Now ya git the FUN of rebuilding the 2nd motor so they have equal output !@
LOL !@ Sorry to be the one to break the bad news to you.
Besides, at this point, it's obvious to all of us you ENJOY this work, sweat and expenditures.
Take Care, Mikey Lulejian - now back home at Lake Oconee, GA

 

[andyak]

Haha! Yeah, I am afraid I will be gradually tacking to Port - I'll have to adjust my tack angle to the boat and local conditions

 

[Scottintexas]

I'm sorry I didn't mention this before but did you make sure the exhaust jackets were clear when you had everything apart? we had a member with a salt water boat and it small holes on the jackets can get clogged. Since you don't know the history of the boat and it was a complete rebuild I wanted to make sure I mentioned it,

Great job and thanks for keeping us updated,

 

[andyak]

@Scottintexas - the block and exhaust I used for this one were from the freshwater Jetski - and the block was cleaned after it was deglazed at the machine shop.

The parts for the third engine will have the block and head from original. I cleaned out the jackets around the Pistons early on - plus that block is at machine shop to be deglazed and then cleaned - so hopefully all is good now.