1990 200 no water out top at idle

[noots]

Got a new to me 200, finally got everything together and ran it today. Getting worried because at idle I have no water coming out the top of the block out of the fitting to the poppet valve. When I rev it up it will start to spray water out of that fitting and then the tell-tale hose. Has a quicksilver gauge and It’s reading about half way, maybe a little over that. I have been shutting it down at this point. Kept an eye on cylinder head temps with an infrared and its reading 170-180. Brand new water pump and base (I did pull it to check it again, seems good)
Has washers in place of the t-stats, assuming poppet is ok.
Any if this seem normal? My 175 would always flow good water at idle.
This is all with the lower unit in a bucket, not on the hose.

[KIRCHNER]

stats and a new impellor

[Turtleherder]

Are you sure you have the water tube fully seated?

[skialot2]

Check the poppet. If it is stuck open the block will not fill up at idol.

[noots]

Brand new water pump base, body & impeller, pulled it off and double checked it too. In the bucket it is definitely pulling water. I will now check the poppet. Tube will be next if that checks out OK. Thanks for the info, fingers crossed!

[rock]

Put it in the lake and see what happens. I have had many that would not flow water till the lower unit was submerged.

Rock

[Jim Speros]

I agree with Rock. No good comes from trying to troubleshoot overheating on a hose, especially from in a bucket.

[pcrussell50]

If your water pump housing is black, you might not see that the black grommet that seals the copper tube to the housing is missing. Ask me how I know? ;)

Also, I have a 1990 2.4/200. It uses the dog bone (two chamber) poppet with a hose barb that runs up to the heads. It does have a slightly weaker telltale (on the hose), than my 2.0/150, which has the simpler single chamber poppet. In the water they are both about the same. Jim and Rock are right about diagnosing the telltale by hose or bucket.

-Peter

[noots]

So here is what I found. Checked the poppet, it had a shorter cut spring for some reason? Put a stock spring back in it. No change. Pulled the LU again, checked out perfect. Even spun the shaft on a drill and got great pressure. Noticed a lot of water dumping out the base of the plate when I put a hose to the water tube. Ended up pulling the power head and found the gasket to look like it had been through hell. Brand new Mercury gasket at that. In the spots where it is broke is where I was seeing alot of water dumping into the can. Still can’t wrap my head around why the gasket would’ve gotten trashed like this. Maybe the wrong one? Anyone out there have the part number for it and the base gasket for the block? I’ve always known them to be the same for multiple years/Hp 534175

[noots]

Part number I had come up with was 27-99177 2 (tel:27-99177 2) for that gasket.
looking back, I may have installed a 27-18307 6. Both are clearly different.

[Jim Speros]

I've changed many engine mounts over the years. I noticed that the mounts can bulge from lower plate from a number of reasons. One is an accumulation of corrosion, while tightening mount bolts the mount can shift. The two plates sandwich the mounts. Make sure the mounts are seated fully . I would hit them down with a no bounce hammer as part of assembly process. These look old and its a fairly involved job the change them. Anyway once you get it cleaned up dry fit without gasket and make sure plates are laying against each other and not rocking on bulge of the mounts.

[skialot2]

I assume you have a carb motor, If your serial # is lower then 0C291519. then you need 27-99177 2. If it's higher, you need 27-18307 6. The gasket in your picture looks wrong

[noots]

Unfortunately no serial numbers left on this unit and it is a carb motor. I think I will go with the other gasket, this one seems to have way too many holes in it for whatever reason as compared to part #27-99177 2. The spots that were blown out were clearly causing a loss of pressure and pushing the water out.

[noots]

Any significant differences in the plate to determine which design it is, I, II or III? This what mine look like.534177

[skialot2]

I think you need this gasket

Mariner & Mercury Marine Outboard Powerhead Base Gasket 991772 | eBay (https://www.ebay.com/itm/364625388321?epid=1424944693&itmmeta=01J2ANVK3BJT1XN61M103WWE77&hash=item54e55de321:g:2B0AAOSwQKBld3KT&itmprp=enc%3AAQAJAAAAwNTtq7LfisuzVMB5CW9F9wyV1c66Ff8%2BErXn3EWgXcfISiOj7K215r9KL3uX5LnCWIUDeY7higgza Xu0OVTCj8GdoPpzf5B78dLGJMPQg03x5IrjpW6mEjL4wQbxfhpfjIhZ9XcZiSfj1h8W6Nd8LGXw6Z0tx7Ab6nyfjJkvxAmsF1F9b b87m0%2BfEqRFaLJlRYqDRTXRDf8X4b7plmbTFyikPenvbnwCPRqQH42AF1zW0Emjjcg4EvixK2lN4vJsmQ%3D%3D%7Ctkp%3ABk 9SR-Sx7tWSZA)

https://i.ebayimg.com/images/g/2B0AAOSwQKBld3KT/s-l1600.webp

Not this gasket

WSM Mercury Mariner V6 110 -200 HP Drive Housing Plate Gasket 510-36, 27-183076 | eBay (https://www.ebay.com/itm/122542664470?itmmeta=01J2AP3D2XZTXCPBCTZC6841WT&hash=item1c881cab16:g:6o0AAOSw~gRVy8Jg&itmprp=enc%3AAQAJAAAA4IzbF84sYB1f6KobTge%2FnKrH2SY9FYhBO%2BuqDjbfrU2Gs8l72pfP1hZM%2BL%2BZHExSSTZvBvk Rna0y01jIMwpM6U6JCVHZV485jE%2F2d%2FssVfn2m5ok6fFAZdbX9kHzp5Bfv2EYq57RpkRo4S67mzxASCRFr4sRdIY5E5Ppmie 6V6%2FNtwy80gE4DTupcBHvrd%2BsKwQewU4b23TUNbZErRcZA2mTmkcxavMr%2BnkuMvlubUen1wTnMIKKx%2Fwz81SKSd2f%2F rElp8%2FazXflBHzkWnyaPgjx11tpK2hKczB2jB4Asf7%2F%7Ctkp%3ABFBMztGN1pJk)

https://i.ebayimg.com/images/g/6o0AAOSw~gRVy8Jg/s-l500.webp

[noots]

Gaskets ordered and on the way. Going to check everything for flatness and clean everything real good. Do a dry fit to double check. I thought about a sealer of some type at least around the water jackets, but I’m assuming that is not necessary as everything should fit properly once tourqed.

[Jim Speros]

It wouldn't hurt to use some perfect seal { Permatex aviation sealant with brush in top } on the edges of center section between mounts where water comes up from. I have seen jobs come it where water was leaking out visible from tiller/ mount area. Be careful when tightening center bolts threads are aluminum. After powerhead is installed you can use a pic to check to see if area between mounts is compressing the gasket.

[skialot2]

I use a sharpening stone to make sure the gasket sealing surface is flat and free of burrs. You can really feel a big difference. I learned that trick rebuilding automatic transmissions. It really makes the valve body gaskets seal much better. You cannot use sealer on them. But I do use sealer on the powerhead /adaptor plate gaskets. I use Indian head gasket shellac. I have never had a powerhead gasket leak.




https://static.wixstatic.com/media/7e6385_ac773932725b4ca786442d7ffe26af4e~mv2.jpg/v1/fill/w_498,h_498,al_c,q_85,usm_0.66_1.00_0.01/7e6385_ac773932725b4ca786442d7ffe26af4e~mv2.jpghttps://i.ebayimg.com/images/g/EU8AAOSwZnBhgYVB/s-l400.jpg

[noots]

First shake down run today. Went very well. Excellent water pressure now! Need to play with the idle and address a fuel line, otherwise very happy. Thank you everyone for the advice and ideas. S&F is the best boating community ever no doubt!
534374

[noots]

(I haven’t figured out how to make a pic look right yet)

[pcrussell50]

(I haven’t figured out how to make a pic look right yet)

its s&f. If you hold your iPhone in landscape mode when you take your shot, the forum software assumes you held your phone wrong and rotates the photo for you. So far the only fix I can recall anyone posting is to just take your photo in portrait mode. Unless I have missed something.

and btw, thanks for sharing your final results. It helps the rest of us learn from your adventures

-Peter

[sonicss33]

534379