Suzuki DT65 water in lower cylinder

[docimastic]

I am writing this post in response to a "what's the history of your engine?" question by mphelle8vld in another post....so I don't get accused of hijacking a post. Incidentally, he (?) was VERY helpful (thanks again)!

Bought (for cheap, $150 - so lots of "wiggle" room to pay for parts, etc. Can part out for more than what we paid....) a 1994 DT65 Suzuki that was getting water in the lower cylinder. Someone had pulled the head..the head head gasket looked fine. Then, he put the head back on.... and it wouldn't come off. One head bolt had broken, and was now stuck in the head. After about 6 hours of work, got the head off ...but only when the head bolt snapped from twisting back and forth, after getting it away from the block/crankcase about 5/16 of an inch. Pretty disappointed with the amount of corrosion in the cooling jackets for an engine that had only been used in salt water for (the last) 5 years.... I guess the owner didn't know about flushing with fresh water. Grrrr. But life goes on. Using a SpeedOut brand of "EZ Out" ...after drilling with a left-handed drill to no avail, the bolt threads remain stuck.... even when part of the casting broke. Double GRRRR. Here's (linked below) how it should look (a different cylinder) and the broken casting with bolt still stuck....even after heating the aluminum to try to take advantage of the different expansion coefficients of steel and aluminum. Am planning to use an aluminum based epoxy to build up he broken part. (I've read online of some very long-term successful block repairs using various epoxies.)

So... I decided to let the head bolt issue sit for a bit, and started on the exhaust cover and exhaust plate, that area being the 2nd most likely culprit of the water in the cylinder. Despite "babying" the bolts...loosen a tad, re-tighten a tad, again and again, several of those bolts have broken off. TRIPLE GRRRR. I mean, what kind of metal (hardness) did Suzuki use on those? No excessive torque at all... Haven't removed them all, yet. (Hey, trying to earn a living gets in the way of projects!)

Will have to pull the powerhead to remove the broken-off exhaust cover bolts, as some are below the lower cowl...so can't drill into them. Not a big deal in the scheme of things.

May have to find someone with a "bolt eater"... that, using electric arc, disintegrates the bolt while leaving the aluminum intact. What an incredible technology! (Check out some YouTube videos on "bolt eater" and/or "bolt disintegration"!)

PS: This is all the fault of my 28 year old son. <grin> He bought a non-running 1967 Mercury 3.9hp outboard. Working on it with him to get it running (replaced the water pump impeller and had the flywheel magnets re-magnetized; also had to replace one fuel pump check valve) was like re-living my past....I worked on / fiddled with outboards all through the 60's (yes, I am that old! LOL)... and so... despite the headaches, I am loving the challenge.

PPS: My son and I are trying to get a real boat (something more than his 10" Jon boat with the 3.9 Merc) on the water and running on a budget that is less than a "beer budget." Bought a 15' tri-hull bowrider in decent shape (nice gel coat, good floor, transom seems fine) with a trailer, for ....get this...$50! Should be sweet with the DT65 on it......

Any suggestions / comments, etc. will be appreciated, of course!

David

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[99yam40]

with water getting into the lower cylinder there is a good chance you have rust on the crank and bearings.
You already know you will have to pull the power head, so take it completely apart before trying to deal with the broken bolts.

See what all you find wrong with it and how many more bolts you end up breaking getting it apart.
A service manual for the motor is another cost you need to add in
and how much you are willing to spend with your time and money before putting too much into it

 

[docimastic]

All excellent points, thanks, 99yam40. I am a bit ashamed to admit that I hadn't thought about the possibility that water has gotten into the lower end/crankcase..... Not sure if I will need to pull completely apart to inspect that...but I might have to, for sure. Pulling it completely apart would sure make it easier to take to a shop for bolt removal/disintegration if I go that route. Also would allow me to acid treat the block to clean up the corrosion, of which there is much. Any thoughts on dunking it into dilute (like 25%) muriatic (hydrochloric) acid? Or maybe vinegar and salt...much milder, will take a lot longer, but so what? The corrosion appears similar - although I think not quite as bad - as that shown in this post: http://forums.iboats.com/forum/engi...-suzuki-dt65-restoration-salt-water-corrosion

I do have the Seloc manual, which is adequate, it appears. Can get a used factory manual for about $40-ish. Might be a good idea; it is tempting... but that leads to your question about how much time and money am I /we willing to put into it - always a good question, but often hard to answer. It's always a tough call to know when to "stop the bleeding"!

For the time being, I am going to pull the head, inspect the lower crankcase, crankshaft, rod, etc.... and see how many more bolts break! Also a good time to check the thermostat, although I don't think that was a problem.

Understand that there is a certain satisfaction in doing this... Well, if it is ultimately successful. LOL Will try to keep that balanced with the time and money idea, per your thoughts/question.

Thanks for your excellent thoughts!

 

[docimastic]

No Title

Here's an update.... I pulled off the exhaust cover and the exhaust cover plate... Almost half of the bolts broke off. On the ones that didn't break, there is NO indication of grease or anti-seize on the threads. Shame on Suzuki! I mean, WTF??? Note in the attached pic that the gasket between the plate and the block appears to have been leaking at the very bottom (you may recall it was the bottom cylinder that was getting water into it...) ...It shows black across the width of the gasket; the remainder of the sealing areas shows otherwise. AND...the carbon on the plate is (relatively) cleaned away.... which (yes, I could be wrong) tells me that water was leaking into the exhaust area at this location. Still haven't pulled the powerhead to check the lower end of #3 for rust, etc per 99yam40's thoughts. But making progress on this project, it seems!