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8V53 Detroit Hydrolock

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cbaymac

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Is it possible to bend a rod by hyrolocking a detroit diesel 8v53 by using the starter? I got water in the aft cylinder, pulled the head, but can not turn the engine over a full revolution using a wrench on the front crankshaft nut.
Thanks you,
Gordon :(
 
I don't know. I think it is possible.

But, how long a lever are you using? Are you sure it's not the compression of the other bank that is holding you up?

If it is a problem with your "drowned" hole like a bent rod or broken ring digging into the cylinder wall, if you keep applying force, it should just start to push the liner up.

If it is SOLID to the point of, with a long lever, you start over torquing the balancer nut then you need to reassess and make sure it isn't something else that locked.
 
jgmo, I have pulled the aft injector on the other bank, but will remove them all as my next step just to make sure the other bank is not the hold up. I am using just a standard 3/4 inch drive set to turn the engine. It goes pretty well one way and then the other for about 180 degrees, but not 360. I had the same problem several years ago, and it was the aft cylinder, but it seems to be fine now as the piston comes to the top, but the liner does try to push out of the block. I locked it down with a large washer and head bolt, but wonder if it will reseal properly. It only came up about 3/8" before I tapped the liner back down and locked her down. More to follow.
 
Hi Gordon,
The liner popping up is not a very good sign. Suggests some undue friction between liner and piston. It normally takes a puller "shoe" hooked on the bottom lip and at least some moderate force applied to the puller screw to get them out. That is if the liner was a good fit in the first place. I've seen some guys just throw liners in without match measurement with an oversize bore and get some real sloppy fit.

But, sorry to say it doesn't look all that good for you from here.

I guess I should say though that, if you can get the pan off, it might be a good idea to unbolt the cap and push the whole affair out and then try and separate them to see what is going on. I think you are headed for a kit there anyway.

Good luck.
 
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igmo, I think you are right, but I failed to note that this is the rear cyl and the one that floods first, and the one that flooded five years ago. I believe I bent the connecting rod at that time by using a huge breaker bar...with out draining the water...i thought the rings had just rusted. What a mess, bent the rod, and even broke the cylinder liner with the bar. Finally got the head off, jacked the engine up in the boat and replaced the rod, piston and liner. The reason I think it came up this time is that there was some minor rust in the cylinder due to the sea water ingestion, but nothing too bad. It does not seem to be the bad rod this time however as the piston comes up flush.

At any rate, I am not sure why I am getting water in the cylinder. Happens when the engine cranks for 30 or 40 seconds, but does not start...had water in the fuel. I can drain the exhaust liner to a certain extent, but the exhaust is dual lined. Not sure how the sea water is getting in. Need to check the riser, the exhaust itself and the head. One post I saw said that some owners have gone to a heat blanket over the exhaust manifold and a spray bar of some sort after the exhaust pipe rise to prevent water from backing down into the engine through the exhaust valves. Looks like another fun six months in the bottom of the boat. More to follow. Thanks.
 
Gordon,
Yes, that is a fairly common problem with marine exhaust systems. The engine's exhaust flow is necessary for moving and ejecting the water BECAUSE of the riser. When the engine doesn't start immediately and the operator keeps cranking, water backs up behind the riser in the manifold and gets ingested through the exhaust valves. Happens on pretty much all engine types. Many skippers are completely unaware of this "trait".

I have always lived by the rule that if she doesn't fire IMMEDIATELY, then you MUST stop cranking and investigate the cause or run the risk of this happening.

Also, as the engine gets worn and tends to crank longer on cold mornings, you might consider installing a starting aid injection system. It has been discovered that WD-40 can be used as an effective starting aid on lower compression engines and will not harm the internals like ETHER has a tendency to do. Most skippers don't know this either so it is my "gift" to you. Keep a can on board if you don't already.

Yes, that sounds like a miserable time down there "in the hole". I'm sorta in that place now with a truck I'm working on but nowhere NEAR as tight of quarters that you will be in that engine space.

Boating CAN be fun, just not this week

Good luck guy,
jimmyd
 
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