Logo
FULL SITE MENU

water in my oil 4.3 mercrusier

P

prospur

New member
Hello Im new here. Has anyone used Sierra 18-3879 head gaskets before? Im try to find out if I put them on right. I have put a 2001 GM 4.3 together and have ended up with water in my oil.
 
most head gaskets have the metal surface down and the fire ring facing up ( the thin band of metal around the cylinder ) I use Permatex Aviation sealant around the water ports on the head and the gasket. Did you use the correct torque sequence and values
 
Bt Doctur said:
click to enlarge
Click to expand...

I did the sequence and torqed to 66ft lbs per a seloc manual.


  1. Position the cylinder head over the dowels in the block. Coat the threads of the head bolts with Perfect Seal, Loctite 565 PST or Loctite 567 PST and install them finger tight. It never hurts to use new bolts, although it's not necessary. Tighten the bolts, a little at a time, in the sequence illustrated, until the proper tightening torque is achieved.
    • Tighten all bolts, in sequence, to 22 ft. lbs. (30 Nm). Next, tighten the short bolts an additional 55°, the medium bolts an additional 65°, and the long bolts and additional 75°. If an angle torque wrench is not available, try 26 ft. lbs. (35 Nm) on the 1st pass, 44 ft. lbs. (60 Nm) on a 2nd pass and then 66 ft. lbs. (90 Nm) on a 3rd pass.
    • On the V6, short bolts are 2, 3, 6, 7, 10 and 11; medium bolts are 1 and 4; and long bolts are 5, 8, 9, 12 and 13
    • On the V8, short bolts are 3, 4, 7, 8, 11, 12, 15 and 16; medium bolts are 14 and 17; and long bolts are 1, 2, 5, 6, 9, 10 and 13
 
Im thinking reinstall intake manifold again and see what happens. maybe a leak at intake. Or would yoy go ahead and pull heads to insoect?
 
Questions:

Were the cylinder heads removed due to an over-heat?
Were the cylinder heads checked for straightness/flatness while they were removed?
Were the cylinder heads magnafluxed while they were removed?
Were the male and female threads clean and dry when you applied the thread sealant?


.
 
Last edited:
I got a answer from Sierra about which way the head gaskets went on and I put them on correctly. Im going to put it back together and see what happens. That's is all I know to do at this point. I am going to seal around the water ports between heads and intake.
 
On intake gaskets water ports, I use gasket eliminator , anaerobic, locktite makes 518. When I worked for Detroit diesel we call it grape jelly..
Did you take a good look at block in valley, especially where lifter journals are those block if they freeze will have a hairline crack just below lifters.
Why did you have heads off?
 
Mikey N.C. said:
On intake gaskets water ports, I use gasket eliminator , anaerobic, locktite makes 518. When I worked for Detroit diesel we call it grape jelly..
Did you take a good look at block in valley, especially where lifter journals are those block if they freeze will have a hairline crack just below lifters.
Why did you have heads off?
Click to expand...


I bought the boat with a known bad engine. It was not winterized and block was cracked. I purchased a short block from an individual that claimed this was a rebuilt block and it looks like it is. I had the original heads checked, magnifluxed and a valve job. Heads checked ok. All I did with the intake was clean it before install. I did look for a crack or damage but didn't see any. There are some bolt holes for the intake that don't go all the way through and I didn't run a tap down through them and Im thinking one of them may have had some gunk in it and I got fooled when I torqued the intake down. Im going to reinstall the intake with some sealer around the water ports and try again.
 
Here is an update on that has been done:


I ran a compression check and all cylinders tested out between 130-140. I torqued the cylinder heads at 65lbs. Did a homemade smoke test on the heads and block by taping off head water ports and putting a tube into the water pump intake hose and taping it off. Blew smoke in this tube and watched for smoke. Did the same test on the intake. At this point we reassembled engine putting sealant around intake gasket water ports and cleaned intake bolts and ports. we installed a new oil filter and new oil. Started engine and ran it for 15-20 minutes with temp at 140. Next we drained the oil and oil was milky, which was to be expected due to the residual oil and moisture in the engine. I repeated this process about 4 times with the oil improving marginally to a light cream milky color. Today, I pressurized the cooling system (see picture) which seems to be holding at 15lbs. Not sure where the water is coming from. How long should the system stay at a pressure to determine 100% no leaks. Any input would be greatly appreciated.
 
Is it a Volvo penta with sea water pump on front of crankshaft?
If your oil is getting less milky, let it run up till thermostat opens. Sometimes it can take 4-5 oil changes , instead of replacing oil filter evertime use 3 filters drain 1st pour new oil after drained let set for a few then pour that oil out, then reuse that filter for getting milky oil out. Most shops probably just use new filters every time. Once oil is not that milky then use new filter. But once oil starts to clear up , make sure to get engine up to temp. To make sure you've fixed problem.
 
Mikey N.C. said:
Is it a Volvo penta with sea water pump on front of crankshaft?
If your oil is getting less milky, let it run up till thermostat opens. Sometimes it can take 4-5 oil changes , instead of replacing oil filter evertime use 3 filters drain 1st pour new oil after drained let set for a few then pour that oil out, then reuse that filter for getting milky oil out. Most shops probably just use new filters every time. Once oil is not that milky then use new filter. But once oil starts to clear up , make sure to get engine up to temp. To make sure you've fixed problem.
Click to expand...

Thanks for your reply. No it is a 2001 Mercrusier 4.3. I have changed oil at least 4 times and it has got better. I did not change filter every time. upon the last time I drained the oil and left the hose open trying to drain as much as posible. As I stated earlier I have a pressure tester attached and the engine held good pressure over night so I'm pretty sure the problem is solved just need to get clean oil. The plan is to install a new filter and do as you have suggested until it cleans up or wont then I'll investigate further. Thanks again for your imput.
 
Bt Doctur said:
what about the manifolds, ?
Click to expand...


I check them the best I could by letting water set in them for a while and watched the exhaust ports for moisture. Nothing showed up. These are the batwing style manifolds. I've heard they are prone to cracks. This boat is a 2001 with about 13 summers on it. The guy before me bought it in 2013, used it four times and put it in the barn for the winter and did not wintereize it. Busted the block for sure.
 
Ok I am totaly stumped. I have changed oil at least six times and it still gets milky. I have pressurized cooling system and it holds 15lbs overnight. Im at a loss and dont know what to do. If anyone would like to call me and discuss my situation I can ues the input. 7657488773
 
I just removed my exhaust manifolds and found water in the port side exhaust. This could be my problem. They are the bat wing type. Whats everyones thoughts on this.
 
That you have a bad block that is pulling water into the cylinder bores and pushing it out the exhaust.
"I purchased a short block from an individual that claimed this was a rebuilt block and it looks like it is."
 
Last edited:
o2batsea said:
That you have a bad block that is pulling water into the cylinder bores and pushing it out the exhaust.
"I purchased a short block from an individual that claimed this was a rebuilt block and it looks like it is."
Click to expand...


I would think that would show up during a compression test or a pressure test of the cooling system. But who knows I'm stumped.
 
Now that you have the exhaust manifolds off the engine, you could fabricate some covers for the connections that normally have water in them. You can then do your air pressure test to see if the manifold is the culprit.
 
The OP pressure tested the block at 15 psi in posts 16 and 17 above. He has water in the port-side exhaust ports. I would think the water is either coming from a cracked block when at normal operating temperature and pressure, or the water is coming from a cracked exhaust manifold. Wouldn't a pressure test of the port manifold help to narrow down the problem?
 
DJR said:
The OP pressure tested the block at 15 psi in posts 16 and 17 above. He has water in the port-side exhaust ports. I would think the water is either coming from a cracked block when at normal operating temperature and pressure, or the water is coming from a cracked exhaust manifold. Wouldn't a pressure test of the port manifold help to narrow down the problem?
Click to expand...


I would like to pressure the manifold but as of yet cant figure a way to do it. They are the one piece manifolds that they call bat wings. any Ideas would be greatly appreciated.
 
Back
Top