What is this hole for?

[imported_rick]

On the starboard side of my 1980 115hp Chrysler is a hole that blows out hot exhaust. Can I plug this hole up or is there a reason why it's open. I'm only concerned because it's blowing directly onto my fuel line and it gets kind of hot under the hood.



Thanks,
Rick

 

[pnwboat]

Re: What is this hole for?

That looks like the port for a brass fitting for the hose that normally goes to your fuel pump. Can't tell from the picture, but it looks like your fuel pump already has the By-pass port hose running to it. Without it, your fuel pump will not work. If so, that open port should be closed off with a brass pipe plug.

 

[imported_rick]

Re: What is this hole for?

Thanks pnwboat!

 

[jerryjerry05]

Re: What is this hole for?

From the looks of the pieces(blue???)Someones swapped a few parts from a newer model.
That is probably the suck for the fuel pump.
Looks like they changed it and just didin't fill the hole.
Post some more pics and maybe we can figure out what's new and old.J

 

[Frank Acampora]

Re: What is this hole for?



That block is NOT a 1980. It is a replacement block and much newer. Judging by the oil recirculation fitting and hose, it would be late 80s to early 90s.

The fuel pump should have a fitting for the pulse hose which would connect to that opening. It would be on the bypass cover behind the pump outlet to the carbs. These photos are from a twin pump set-up but they clearly show the 90 degree fitting. Without it you are operating on only the large primary part of the diaphragm. The secondary is not getting any pressure and vacuum pulses. AND, you are losing pressure and vacuum on that cylinder so it is not delivering all its potential power.

Does the engine tend to run out of fuel at full throttle?

 

[imported_rick]

Re: What is this hole for?

Yes, it's a newer block, the block is not 1980.

The original was seized. The block was replaced and all the external stuff on the original block was put on the new one. I'm at work right now (Aston by the way) so I don't have any other pictures available to post for the moment. The original block only had one fuel pump.

I ran it in the Delaware for the first time back on July 15 for only about an hour. I didn't take her over 20 mph the whole time. I started with 6 gallons of gas and after the one hour test ride I had more than three gallons left. Never took it to WOT. She ran pretty good the whole time. On my return to the ramp, about a half mile away or so, my steering broke so we just kept it at about 6-10 mph til we got to the ramp. Idle was a bit rough, adjusted the floats the other day, will have to see if it makes a difference next time out.

I agree that I'm losing pressure on that cylinder, just didn't realize til afterwards that hot exhaust gasses were coming out of that hole. I'll post some more pictures tonight when I get home.

 

[Frank Acampora]

Re: What is this hole for?

They are NOT exhaust gases. They are hot because the engine is hot ---BUT--- they are a fresh charge of air/fuel. SO: We know that in the presence of spark, air/fuel ignites. Do something before you run the engine again! Plug the hole or attach the 90 degree fitting and hose--but do something.

You can get a barbed 90 degree fitting in the plumbing section of Lowes or Home Depot for a buck or two. I think the size is 1/8 NPT. However: Aston (Pa) is not too far from me so if you wanted to ride over after work and get a fitting, send me a Private Message.

 

[imported_rick]

Re: What is this hole for?

Sent you a message Frank.

Thanks,
Rick

 

[imported_rick]

Re: What is this hole for?

Here are some more pictures

 

[pnwboat]

Re: What is this hole for?

I looked at picture number 2 that shows your fuel pump. Looks like it may be the older style. The open port on your block usually has a 90? brass elbow and attaches to the newer style fuel pump using the hose that my finger is pointing at.



Not sure your pump has the fitting for that hose. Nice restoration by the way!

 

[imported_rick]

Re: What is this hole for?

Thanks for literally pointing it out for me pnwboat.

I never even noticed that little bugger.

And thanks Frank, for the part and for your time and tour of your Chrysler collection last night.

 

[BobList]

Re: What is this hole for?

Ok, back up here guys...... you're saying that if that "pulse" hose is loose, or fell off, you would have symptoms such as: late timing, no power, the feeling of not enough fuel, raw fuel smell, and generally poopy top speed and a s l o w climb to high rpms?... like, if for instance, after reading this thread, after coming off the water with a no-power- gonna rebuild my carbs kinda day and fix this Satan possessed Force 125 that every ten minutes runs great, then crappy, and I went to the driveway and pulled the cowl off and found "my" pulse hose loose and practically DISCONNECTED.... that definately can make the engine run bad?

Sometimes I wish I wasn't an auto mechanic.. I pegged that hose as a "breather", no big deal, it never had a clamp on it anyway.

I think you guys just fixed my Force from Hell. I can see where this hose intermittantly was sealing, then not, then sealing.. Dang.

Bob List

 

[imported_rick]

Re: What is this hole for?

While the motor ran without the hose, it did run like crap at idle, actually stalling out at times from lack of fuel I guess. After installing the hose and adjusting the floats, I took the boat out yesterday and in ran flawlessly!

 

[BobList]

Re: What is this hole for?

did it generally run smoother and faster? Started immediately, no excess cranking?