Johnson tn28 water stream question

[scottw]

I am still looking for the "outlet" near the bottom of the cylinder head where a water stream should be present to verify the water pump is operating. I see all sorts of videos online that show this stream near the low speed adjustment needle but I can’t see an outlet hole for the stream on mine. It appears to be a hole drilled into an elbow but I don’t know the hole diameter. Any thoughts?

[fisherman6]

It should be a drilled hole in an elbow just as you said. It is quite a small hole if I remember correctly. I have a TN-26 in pieces. If I get a chance this evening I can try to get a picture if no one has posted one yet. It seems like the hole is around 0.03" or so.
-Ben

OldJohnnyRude on YouTube

[frankr]

Yes, a small hole drilled in the bottom corner of the copper pipe elbow. I don’t know the diameter off-hand. Probably somewhere between 1/16" and 3/32" as a wild guess.

EDIT: Written at same time as Ben was typing. At least we agree.

[steveh]

It is a very small hole and is easily covered with paint, grease, etc…

[scottw]

Wow, thanks both of you guys for responding quickly. Hopefully, it is a thick layer of paint that is obstructing the hole. I bought this motor from Craig’s list and the previous owner had recently painted it. If no hole is present, I’ll drill one. The motor right now seems to run well for 5-8 mins at top end then slowly decreases rpm’s until stalling.

[2fast4me]

Scott, is your vent open on the gas cap? Is it plugged with old varnish? Fuel flow will stop with that vent being restricted.
Jim

2Fast4Me

[1946zephyr]

I wouldn’t drill it out, because it’s probably already present. Just take a small wire and clean it out.

[fisherman6]

I would not recommend drilling it out either. Unless someone replaced it with another elbow, the hole is already there. I’d try some lacquer thinner on the elbow until I found the hole then clean it out with a wire or something. If the water pump is working the powerhead will still get cooling water regardless if this tell tale hole is flowing. On the other hand, just because this hole shows water flow does NOT mean the powerhead is seeing the cooling water. I believe on these motors this hole is actually in the system BEFORE the water passes through the powerhead. Someone correct me if I’m wrong on that. Flow at the tell tale shows the pump is pumping but that is really all it tells you in this case.
-Ben

OldJohnnyRude on YouTube

[scottw]

Gentlemen,
Thanks for all of your input. After grinding away the paint….. and using a small wire… Here is the hole that was missing. Another issue has arisen, The motor is leaking with the petcock for the fuel turned off. It appears to be leaking in the junction where the primer pump and the top of the carb meet. The original owner of the engine was kind enough to take a look at it.

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