Suzuki DT40 (Water in Cylinder)

[TGBTG7701]

I have a 1995 DT40 2 stroke outboard, that I am getting water in the bottom cylinder. I bought the boat and motor from a friend, he had the head gasket replaced about two months ago. I have 125 psi compression on top and 120+ psi on bottom cylinder. I am not an outboard mechanic, but I have built race engines for 20+years, and something does not seem right to me. I took the motor to the guy that repaired it a few months back, and did not get the feeling he knew what he was talking about. I asked if he checked to make sure the head was not crack and also make sure it was flat. He said there was not a need to check those things, he also used Gasgacinch on the head gasket, I have used tons of this stuff, but never on a head gasket.

I talked with a Suzuki outboard dealer, they said he should not have used gasket adhesive, checked to head for cracks, and made sure the block and head was flat, run the engine for about an hour, let it cool down completely and re-torque the head bolts, by doing it this way, I should not have any problems.

I know this boat and motor, bought it from the original owner, it has never been in salt water, always flushed, never ran hot, and always serviced.

Will the head gasket blow, even with everything is working correctly?

[mphelle8vld]

You didn't say how you determined water was in the lower cylinder, or whether your friend had the same issue before the new head gasket. The compression numbers are good but a leak down test would tell you if the metallic seal around the cylinder was intact and not leaking water.

It is also possible for water to enter through the exhaust port from a leaking exhaust cover gasket.

[TGBTG7701]

[QUOTE=mphelle8vld;21806]You didn't say how you determined water was in the lower cylinder, or whether your friend had the same issue before the new head gasket.

There is a miss about about 3/4 throttle, so I pulled to plugs, found the bottom plug wet, with a slight brown milky deposit around the electrode. My friend did have the same issue, when the mechanic checked it, there was only 85 psi of compression at this time. The main thing that bothers me, the mechanic shop does not warranty their work but is only a few dollars an hour less then the dealer, which has at least a 90 day.

[mphelle8vld]

Hard to find value in today's service industry, I'm sure you have the skills to re-do the gasket job correctly, checking surfaces for flatness and following the Suzuki techs advice. A proper factory service manual would be a good investment now that you are entering the wild world of two stroke outboards! Keep us up to date with your progress, will help wherever possible.

Get a can of fogging oil and soak the innards asap.

[TGBTG7701]

I spoke with the shop that has my boat, he told me "I do not know what is wrong, not sure what else I can do". He pulled the head, but can not tell me if it is good, he does not even have a straight edge to check for flatness. He took a file and ran it across the mating surface of the head, left fairly deep gouges in the aluminum, not good. I ordered a new head, gasket and bolts, along with a new head cover and gasket for it. The cylinders have some corrosion around the bores, some pitting, but there looks to be a little over 3/4 of the matting surface of the bore looks good, inside the bore looks decent.

I plan on putting the head on, running the motor, then performing a leak down test and hope for the best.

[mphelle8vld]

Is this this the same shop that used gasket sealer on the head gasket or another bad shop? Sounds like the Jethro Bodine Marine and nail salon. Let us know what the results are with the new parts.