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TAMD41P possible PCV problem

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bmac8369

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"I am the new owner of a 28&#3

"I am the new owner of a 28' Topaz with twin TAMD41ps. Last night we were on our way out to do some stripper fishing (about 3200rpms) and the starboard engine lost oil pressure and i shut it down. I was watching the gauges and saw it drop so i shut it down. When i opened up the hatch oil was all over the vavle covers and top of the engine. The breather line coming off the valve cover was off. So we checked the oil level and noticed it was low. Added the proper amount and restarted the engine. It fired up like normal and sounded ok. About 10 seconds later the breather line on the vavle cover popped off and oil began coming out of the dipstick tube. So we shut it down and went back to shore on the other engine. My question is what is the cause of this, PCV messed up? ALso what damage was suffered."
 
I only see 2 possibilities:
1

I only see 2 possibilities:
1: Blown hole in a piston. but not likely if engine performes.
2: Your crank case ventilation system is blocked.
 
Mort thanks for the reply. My

Mort thanks for the reply. My first thought was plugged crank case vent. I can not find a crank case vent on my TAMD41P. My mech said it doesnt have one. Could this by true?
 
Should be the silver can in fr

Should be the silver can in front of the air cleaner cover. I have the B model which is almost the same config and was talking with the
mechs today and they say the crankcase vent. sys. is a reliable system. Does your engine have this can? It might be mounted on a check valve of sorts.
 
"I do not think the 'P&#39

"I do not think the 'P' model have that filter, I do not find it in thee parts breakdown.
Anyway, all engines have a crank case ventilation system, one way or the other. They just need to get rid of the pressure build up.
Your hose popping off is a clear sign that pressure gets too high.
Follow the hose, where does it attach?
Is it a blockage in the valve cover where it attach to?"
 
"These are listed for the TAMD

"These are listed for the TAMD41P-A, I think...
Maybe they are options? Maybe Morten can clarify.
49 Crankcase ventilation 838763
50 Check valve 858256
51 Spring pin 95197152
52 Steel ball 181501
53 Gasket 843449
54 Filter 876069"
 
"thanks guys for the replys.

"thanks guys for the replys. I am just at a loss here. The engines only have 800hrs. I cant believe I am having these problems after my first trip on the boat. Sailor, do you have a schematic showing the #s you listed? Thanks for all the help."
 
"There are some different &#39

"There are some different 'versions' The 'D' type has 3 equal inspection covers and no filter.
The A, B and C has a different filter and no ball-valve.
Then what is on the pick is P-A?
All a jungle, try to figure out by searching on the engine.
On the (A),B and C types the hose from valve cover (if modified) goes to behind the air filter."
 
"Mort,
Which part # is the Ba

"Mort,
Which part # is the Ball? Thanks so much guys. I am going to the boat tomorrow and get the numbers so i can get a book."
 
"I was told the valve is for S

"I was told the valve is for Solas qualification.
I was told it's purpose is to keep water out. If equipped, it should spin off with a couple of turns and then can be easily checked. This is something a mechanic would not overlook, so I wonder if you have something different. It is also very possible to have the filter without the check valve, which is the way my B is set up."
 
"Hello Brett,

Sorry for the

"Hello Brett,

Sorry for the late reply, but I just registered for this discussion group today. You may have this issue solved by now, but anyway, I believe my AD41P has the same CCV set-up as yours. The third rocker-arm cover (over cyl. 5&6) has a vent port with a plastic tube (going 90 degrees) back to the air cleaner housing. Under this third rocker-arm cover is the CCV oil separator/filter which is nothing more than a folded brass-alloy wire within a vented plastic cover.

I'm not a AD41P-A history expert, but I believe that this is CCV design was used for engines with serial numbers greater than 2204141572 (mine happens to be 2204153329). Prior to this serial number I believe the can-type CCV filter was used (attached to the third inspection plate on the cylinder head). See the pdf file attached and note the comment regarding S/N in bottom right corner of page 1.<center><table border=1><tr><td>http://www.marineengine.com/discus/icons/mime_pdf.gif""" align=left alt=""application/pdf"">AD41A Cylinder block and Flywheel cover
[url=""][b]CYLINDER BLOCK AND FLYWHEEL COV0.pdf[/b][/url] (52.9 k)</td></tr></table></center> This shows the older can-type CCV filter.

Anyway, on engines with later S/N, the crankcase pressure is relieved up through the small oil drain holes for the rocker-arm shaft assembly, then up through the #3 valve cover [wire mesh] CCV filter, which is then directed via a small plastic tube back to the aircleaner housing and sent right into the intake/compressor fan.

If the oil drain holes for the rocker arm shaft assembly are plugged up, or more likely if cylinder blow-by is really high, the oil will probably not drain and eventually blow the plastic return hose off the port on rocker-arm cover. The other place where oil will be ejected from the engine with high crankcase pressure is through the dip-stick tube.

What did you eventually find out about your particular problem?

/D'oH"
 
Thanks for the reply. Basical

Thanks for the reply. Basically mine is just the vent tube off the valve cover back to the air cleaner. Unfortunately it wasnt the problem. I had 2 dead holes and had to rebuild the engine. I just got it back yesterday.
 
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