Blew up my 300X this weekend. Looking for reputable rebuilder in Michigan.

**dbcycleparts** · 07-22-2018, 01:09 PM

Blew up my 300X this weekend. Burned a hole through the center port side piston, others appear to be okay still. A little concerned what caused the one to go bad? Just prior to the blow up, I notice the last couple of times I was out in the boat the tach needle was bobbing all over when it was above 3-4 thousand rpm, it seemed to run fine, but it was down a couple of mph off the top end speeds it typically would run (I assume the piston was melting down the last couple of times out and just finally let loose). My first thought was it was a faulty or dirty injector? But I have been reading there can be issues with the coil drivers in the ecm and it can cause timing issues which can lead to a melt down on a cylinder (wondering if this has something to with my tach needle jumping around). Motor had around 450 hours on it and has always run perfectly fine until this. Looking for at least a good machine shop in MI that is familiar with doing blind hole outboard motor blocks. Possibly would also like to have a shop that can clean the injectors and reset the ECU to break in and check the drivers in them to make sure ECU or coils were not an issue. Looking for recommendations in the MI area. Thanks.

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**flabum1017** · 07-22-2018, 03:14 PM

Best off to call Jay Smith Racing.......

**Chaz** · 07-22-2018, 03:55 PM

If you want to keep it in Mich. then Capt. Insane-O is your man .. !

Lynn .. PM that man your number

**dbcycleparts** · 07-22-2018, 06:25 PM

Originally Posted by Chaz

If you want to keep it in Mich. then Capt. Insane-O is your man .. !

Lynn .. PM that man your number

Please do! Thanks.

**sonicss33** · 07-22-2018, 07:00 PM

What’s going on with the piston above the bad one?

**capteliminator** · 07-22-2018, 07:25 PM

Second for captninsano.

**dbcycleparts** · 07-22-2018, 07:26 PM

Originally Posted by sonicss33

What’s going on with the piston above the bad one?

Nothing that I know of. Carbon in it is a little darker than the bottom hole and there is a little oil on the bottom lip of the sleeve on the top bore in the photo. Bore from what I can see looks to be fine. Have not pulled the motor all apart yet to inspect further.

**aggiestckl** · 07-22-2018, 07:56 PM

Jay smith does not build 3L

Best guy to deal with is Quinton.

The 300x they build are top notch

**Chaz** · 07-22-2018, 08:09 PM

Originally Posted by sonicss33

What’s going on with the piston above the bad one?

Welp , you can see it's got an eroded sleeve @ the deck sealing area .

**dbcycleparts** · 07-22-2018, 08:21 PM

Originally Posted by Chaz

Welp , you can see it's got an eroded sleeve @ the deck sealing area .

Deck surface is nice and not eroded in person, that is just some oil on the bottom lip. Also the piston is not cocked, it looks that way in the photo for some reason, but in person is it nice and straight.

**Chaz** · 07-22-2018, 08:30 PM

So your sayin I needed my glasses for both issues ... LOL
I stand corrected sir .. !
I looked and said to myself , thats right where this other one I got here broke the crank . And that sleeve looks eroded pretty bad , even though the piston hasn't been steam cleaned … Then I said no need in speculating … but only took down crank part .

**dbcycleparts** · 07-22-2018, 08:37 PM

Originally Posted by Chaz

So your sayin I needed my glasses for both issues ... LOL
I stand corrected sir .. !
I looked and said to myself , thats right where this other one I got here broke the crank . And that sleeve looks eroded pretty bad , even though the piston hasn't been steam cleaned … Then I said no need in speculating … but only took down crank part .

You just made me go double check though!!! LOL! Popped the head off again and the deck surface it nice and smooth, you can see the gasket was sealing fine, and the piston is nice and square in the bore and travels smoothly when you turn the motor over. The motor initially stuck the piston and stopped, but after it sat for a second unstuck and fired right back up. I could have made it back to my folks cottage, but I could hear the piston rattling a little when it started so I shut it right back down and did not want to chance hurting the block or crank by running it any more than I had to.