Hot Air/ Solonoid choke & Air Recirc

[jdcoombs]

My 1969 40 HP has the HA/S choke. There is a port to receive a fitting, which I presume is for a hot air return tube. There is another port on the crankcase cover, I presume to receive the other end of this tube. Correct?
But there is another port in thecrancase cover. What is it for?
Thanks. Y'all helped a lot w/ my water pump issue.

 

[F_R]

Re: Hot Air/ Solonoid choke & Air Recirc

There is a heat exchanger inside the exhaust cover plate. Air flows in one of those ports, through the heat exchanger, out the other port, through the metal tube to the choke housing on the carburetor, where it heats the bimetal spring on the choke. From ther the air flows through passages in the carburetor to the intake manifold, where vacuum makes it all happen.

Obviously, the one port on the heat exchaner must be open to allow air to get into the system.

 

[jdcoombs]

Re: Hot Air/ Solonoid choke & Air Recirc

Thanks, Cap.
I see I thought the gasses flowed the other way. So the hot air goes FROM the exhaust chamber to the choke? I have three open ports. Two in the exhaust chamber, on in the choke. how do I connect the tubes or plug ports? I will have to make them, as there are none.
Also, one of the bolts holding the starter on (one of the 2 under the carb) is stripped and missing. LOTS of smokey gasses come out of the hole. Why? I will tap and helicoil or over-size, but don't know how critical.
Any help or direct me to text?
Thanx
JDC.

 

[F_R]

Re: Hot Air/ Solonoid choke & Air Recirc

There is supposed to be an elbow fitting in the upper hole, with a steel tube from there to the choke on the carb. picture and part numbers at http://epc.brp.com/default.aspx?brands=ej&lang=E

But lets back up a bit. Are you telling me that smoke comes out the two heat exchanger ports on the side cover? That means the heat exchanger is burnt through and must be replaced. Or, if you don't want to do that, then at least plug both holes with a couple of 1/8" pipe plugs. Do not plug the hole in the choke housing. That air flow is included in the calibrated air/fuel intake mix.

Now, the starter mount holes. You say SMOKE comes out there? I can't imagine that. If anything, they might go through into the crankcase. There is no smoke in the crankcase. At least there better not be, or you have big problems. Air and vaporized fuel, yes. Smoke no.

 

[jdcoombs]

Re: Hot Air/ Solonoid choke & Air Recirc

Thanks, F_R. The link was quite helpful. I'll take the Ex cover off and check it out; replace the heat exch if need be. But if the pic is accurate, I seem to be missing the Outer Exhaust cover. Why 2? If that's the case, I'm not sure how the choke tube would get back there, but I'm sure I could figure it out. Where the heck would I get one of those?
The lower bolt puffing out smoke, may actually go thru to the exhaust chamber. Not sure, but I'll check. As I said, I know nada bout these 2 cycles. Seems like black magic to me. Engine runs fine (w/ cover off) so what "big problems" might I expect w/ smoke in crankcase?
Thanx