recirculate check valves 175 evinrude intruder

jtcarter

Petty Officer 1st Class
Joined
Apr 26, 2008
Messages
226
Well here we go again. I took the recirculate check valve lines loose to see if i could find a clog. Well my check valves are in behind the carbs on the manifold anyway. I was trying to blow through them from the block side to the carbs and no flow that way. I tried pulling air and got fuel on two of them and nothing on the other am i checking these right or should i try a syringe and some isoproyl? One won't do anything i can't get it to flow air either way. I haven't checked the other side yet.
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: recirculate check valves 175 evinrude intruder

On the 175 the recirculation check valves are in the face of the intake manifold so you really need to take the carburetors off to replace or work on them.

The isopropyl alcohol will sometimes dissolve gum in the valves and does no harm as long as it is the hardware kind (the drugstore stuff is full of water and says so on the label).

The id of the valves is quite small, so don't expect the alcohol to rush through, it should just move easily. It is just as important that nothing flows back through the valve.

I get those plastic syringes from my dentist, by the way, Monoject 412 is what they are called. http://www.kitkraft.biz/product.php?productid=1460&cat=0&page=1&gclid=CIiJ4Lzy75QCFQJtFQodwzO6qg
They use them for squirting fluids between teeth.
 

jtcarter

Petty Officer 1st Class
Joined
Apr 26, 2008
Messages
226
Re: recirculate check valves 175 evinrude intruder

If i get that deep into it i may as well change all of the check valves. I was looking for a easy way to check them without have to take off the carbs. Book says the flow should go from block to carbs. Why is it that i can't blow through them that way? Shouldn't i be able too. When you pull air from the recirculate line that goes into the manifold to carbs i get fuel is this right? One of them you get no flow either way. I'am just trying to make sure there is a problem before i tear into them. I 'll have to take the manifolds off to get them out i had hell trying to get one of them out before. I have the brown manifold gaskets if i take them out do i need to get new maniflod gaskets or can i retorque these?
 

CatTwentyTwo

Chief Petty Officer
Joined
Jan 11, 2005
Messages
425
Re: recirculate check valves 175 evinrude intruder

I have a 94 175 Johnson and this is how the factory manual says to check them. With the engine running at idle, remove the #1 cylinder recirculation hose from the fitting on the cylinder block and submerge the end of the hose in a cup of water and check for bubbles. Check all recirculation hoses before proceeding. Stop the engine. If bubbles appeared, check the block fitting with a syringe filled with alcohol. If the alcohol flows freely, the #1 cylinder recirc. system is okay. If it is restricted, you need to clean the cylinder block fitting.
If no bubbles appeared, remove the recirc hose and inspect it. If it is damaged, replace the hose and test again. If the hose is okay, you will need to remove the carburetors and intake manifold. Remove the #1 cylinders two check valves and check the manifold hose fitting with a syringe filled with alcohol. If alcohol flows freely, replace the two check valves. If the flow is restricted, clean the fitting and screen. This goes for the other cylinders as well of course. I hope this makes sense, the manual has some pictures to aid in the description.
 
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