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Using Engine Block Sealer


KEWeyand's Avatar
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07-28-04, 02:46 PM   #1  
Using Engine Block Sealer

I hope someone can help me with this - For various reasons, I couldn't get my 1994 18' Larson with a 3.0 Ltr Mercruiser winterized and it appears that I cracked the block. It still runs fine but the oil gets milkey. A car mechanic told me that block sealers have really improved and if I could plumb a radiator into the cooling system and close it all off, there was a good chance that I could get it sealed and avoid the cost of replacing the engine.

What would it take to do the required temporary modifications to the cooling system? It would only have to run about 1/2 hour in that condition.

 
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kpg712's Avatar
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07-29-04, 05:13 AM   #2  
Posted By: KEWeyand I hope someone can help me with this - For various reasons, I couldn't get my 1994 18' Larson with a 3.0 Ltr Mercruiser winterized and it appears that I cracked the block. It still runs fine but the oil gets milkey. A car mechanic told me that block sealers have really improved and if I could plumb a radiator into the cooling system and close it all off, there was a good chance that I could get it sealed and avoid the cost of replacing the engine.

What would it take to do the required temporary modifications to the cooling system? It would only have to run about 1/2 hour in that condition.

what do u mean it would only have to run about 1/2 hour? i don't think any block sealer can cure a cracked block. are u sure the block is cracked? have u checked the manifold for a crack?

 
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07-29-04, 10:39 AM   #3  
There was also a very small crack on the outside of the block, just below the soft plug. How could I tell if the manifold is cracked? There is water in the oil which I thought would indicate a cracked block. I would be very happy if it was something else.

From what I have read about the new generation of block sealers, if you use them according to directions, they will do a good job of sealing cracks. I'm just trying to save this engine as I don't think I can afford to replace it.

Any help you can give will be greatly appreciated.

 
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07-29-04, 05:05 PM   #4  
There was also a very small crack on the outside of the block, just below the soft plug.
if you mean the crack goes up there by a freeze plug. I ythink you should just start looking for a new short block

It still runs fine but the oil gets milkey.
Id stop now till fixed. Could lock up on out in nowhere

ED

 
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07-30-04, 03:21 PM   #5  
u can have the manifold & riser pressure tested. they don't last forever. but, i must tell u that if u have a crack in the block it is probably gone. the repair will be costly. the other poster is right about running it with milky oil. if it hydrolocks u may damage the pistons, etc. there a few things that can cause milky oil. but, if the engine wasen't winterized that is probaly the reason. sorry.

 
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08-05-04, 12:32 PM   #6  
Cracked Manifold?

Could a cracked manifold cause water in the oil? I'm still trying to figure this thing out but at the same time, I am taking your advice and trying to locate a replacement engine.

Thanks for your help.

 
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08-05-04, 06:13 PM   #7  
if u go for a replacement engine, contact mercruiser directly. be wary, very wary of these outfits that offer replacement engines that u see in autozone, pep boys, etc, etc. they don't honor they're warranties. if something goes wrong, they will find a way to blame you. buyer beware!

 
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08-09-04, 06:01 AM   #8  
hekman
Could a cracked manifold cause water in the oil?

>Could a cracked manifold cause water in the oil?

It certainly could. If the crack extends from a cooling line into the crankcase or a piston you will get water in the oil. There are also other ways of getting water in the oil -- through leaky seals, ingesting water through your air intake... Did you hose the engine off and get water in the carbs, or leave the top off in the rain? You may want to flush your crankcase by changing the oil once or twice, then try the motor again and see if it gets cloudy again. Run it at idle and shut it down to check oil frequently before you trust it at higher speeds or away from shore.

You should also remove all your spark plugs and check the insides of your pistons. If one plug or piston shows signs of rust, that would likely indicate a crack in that cylinder.

Ben

 
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08-13-04, 03:48 PM   #9  
I may have found a replacement engine for this boat. It is supposed to be a year 2000 3.0 Ltr just like mine, only newer. The owner purchased it to put into an older boat with a Gen I Mercruiser stern drive and just has not had the time to get it done.

My boat is a 1994 Larson. I'm assuming that it has the Gen II Mercruiser and this engine should bolt right up. Is that correct?

What should I check or look at to reasonably assure myself that the engine is okay? Any tips here?

Thanks very much!

 
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