Poppet Valve

Hello everyone,

I have been working with an overheating issue on my 1997 200 EFI Mariner Magnum. (previously posted as a 1996...duh!). My symptoms are as follows: When I launch the boat, sometimes I get the steady alarm fairly quickly after launch, but other times only after a short run and after coming off of plane. Other times, I get it when at idle. The other day I removed the thermostats and checked them and they both opened up at 143 degrees. My tell tail stream is not super strong, but it never has been really. I have ordered an impeller kit and two new stats just to be safe. My question is does this motor have a poppet valve? I have a Seloc manual, and it doesn't really show it for my model, but it isn't the greatest manual either. It is my understanding that the valve opens up and lets excess water out through the prop exhaust when the pressure in the water system reaches a certain level. Just wondering if anyone knows if this model has a poppet valve and where it might be located. Model # OG486920 Thanks!

Re: Poppet Valve

Hey Badhog1

http://www.crowleymarine.com/mercury-outboard/parts/1679_130.cfm
It's parts 11 thru 22. Let us know if ya need help installing the 'guts'.

The poppit is at the bottom of the block there. Sometime you can get away with replacing just the diaphram. But if it's real nasty in there I usually replace everything there,except the hard bushing that gets pressed/tapped into the head just to be safe. That hard piece lasts a long time.


DamianJP

Re: Poppet Valve

hog;

Engine comes up as a model 7200413FD.

Parts Listing:

http://www.crowleymarine.com/mercury-outboard/1679.cfm

Look under EXHAUST MANIFOLD AND EXHAUST PLATE, item 20

Service Manual:

http://1manual.com/Mercury manuals/Service Manual PDFs/TwoStroke/824052r3/cover.pdf

Gerry

Re: Poppet Valve

Sorry Damien, I stepped on you.

Gerry

Re: Poppet Valve

Nope your fine

More info/help the better. As long as the cooling problem gets fixed, it's all good.

Hog you might have to open the PDF manual in a PDF viewer to be able to click the sections.I have to, if not when I click each section it brings me back to the front cover.

DamianJP

Re: Poppet Valve

Awesome info guys! Thank you! Hopefully this will get me started toward fixing my cooling (or should I say not cooling) issue. When I had the thing on the muffs in the yard the other day, it ran for a long time both at idle and with some revs without ever getting overheat alarm. We took it to the local water hole and it did it soon after launch. I am thinking the impeller will fix it. The whole time it was on the muffs, I was shooting both heads with infrared heat tester, and neither one got above about 165 degrees. The starboard side did run a little hotter that the port sometimes, but at idle it would range from 120-148 degrees. Just thinking that the forced water pressure from the hose at the house is making it stay cool maybe, doing the job for the pump. I will definitely repost to let you know how I make out. Thanks again!

Re: Poppet Valve

To tell you the thruth Im still figuring my XR4's cooling problem. Mines fine when in neutral, idle all day on muffs and stay at half temp. But in gear it will climb to Hot then alarm goes of shortly after. Good luck and lets us know what happenes of if you need more help.

DamianJP

Re: Poppet Valve

Ok, got time to get the poppet valve assy apart and inspect the diaphram and everything. It looks ok, but going to replace the guts in there anyway while we're in there. Also pulled the lower unit and inspected the impeller, it had some wear and one of the vanes had a small chunk missing out of it, so that was probably the problem. Ordering parts today, overnighting them, hopefully we can test sometime this weekend!

Re: Poppet Valve

badhog1 said:

Ok, got time to get the poppet valve assy apart and inspect the diaphram and everything. It looks ok, but going to replace the guts in there anyway while we're in there. Also pulled the lower unit and inspected the impeller, it had some wear and one of the vanes had a small chunk missing out of it, so that was probably the problem. Ordering parts today, overnighting them, hopefully we can test sometime this weekend!

Click to expand...

That's the main problem. Hopefully you didn't mess around with the overheating till you cracked an exhaust divider or something.

Most of us V6 owners consider water pump service to be an annual, spring maintenance item.