2001 merc poppet valve

gbf03 · #1 09-20-2005, 03:34 PM

I am haveing a problem with my 2001 merc 150efi overheating at rpms below 3000. I changed the water pump and lower gear case oil with no success in solving the problem. Someone told me that it might be the poppet valve?
My question to you guys, is this a feasible job to replace the poppet valve for a non mechanic and where exactly is it located on the engine?
Thanks,
George

NoBones · #2 09-20-2005, 05:22 PM

Hi George,
You did not say if you are going by the heat horn or a
temp gauge? The pop-it valves are not that bad to service
as well as the thermostats. Your local Merc dealer should
have a shop manual which spells out step by step how to do this. A minimum of tools are required for this job.
Good Luck, and good to hear from you again, See ya, Ken

gss036 · #3 09-21-2005, 03:20 PM

I think the 1st thing to do is replace the thermostats, they do have a tendency to have salt build up.
The poppet valve is located on the starboard side at the bottom of the block. The lower cowling will come off and make it easier to get to the 3 bolts that holds the cover on. Maybe go to Merc Express parts page and take a look. ttp://www.mercurypartsexpress.com/Pa...00060224064276

The overheat is a constant BEEEEEEEEEEEEEEEP. Over heating in that range is common poppet sympton. About 3000 rpm, (as pressure builds) the poppet opens and dumps excess water thru the exhaust. Both fixes are fairly cheap for parts, although the EFI parts tend to be about twice the price of carbed models.

gbf03 · #4 09-21-2005, 08:58 PM

Thanks guys I am gonna look into it this weekend when I get a chance. The alarm was at a constant beep and the temp guage was in the red when it happened.
thanks
George

Bigshrimpin · #5 10-07-2005, 09:48 PM

Good Poppet information off iboats.

http://www.iboats.com/cgi-bin/ubb/ul...=019921#000001