65 365 really rough idle

[Guest]

Re: 65 365 really rough idle

My car sat for some time but always had a mix of ethanol free and race gas in it. The rear float valve was leaking so I replaced both (very clean in the bowls) changed the power valve per specs and the accel pump

It is very rough at idle 800 and varies 200 rpm high and low. Cruising the highway at low speed it like riding a bucking horse. Give it a little gas or floor it and it runs like a 365 should.
Initial timing is set to 10 and vacuum advance brings it to about 25 degrees. Checked vacuum hoses, checked for vacuum leaks on the intake and carb using brake fluid and all ok. new points rotor and cap. choke ok
Do I just have a carb issue or could it be something else?

Has anyone check for any warpage on the metering plate and carb. housing this would cause a vacuum leak and a lean mixture for sure ,not all Carburetors are rebuild probably .

[Bob H.]

Re: 65 365 really rough idle

I have been searching for a B28 which is not an easy task. Autozone and NAPA no longer have them. Fortunately, I have a friend with a parts warehouse in his garage!. I am getting one from him. The carb will be completely gone through and will get what it needs. Will be check for warping as well.

Thanks for the information guys. I will update when I get the carb back and installed.

[Duke W.]

Re: 65 365 really rough idle

Recently the only B28 available is the Airtex 1053V, but they appear to now be in short supply. Keep looking. Do a Web search. I know some guys have bought several as spares, so you might be able to find someone who will turn one loose to you.

Duke

[Duke W.]

Re: 65 365 really rough idle

Bob,


Take Duke’s advice and replace the B3 vacuum canister with the B28. I had the same issue with my ‘65 L79. I had a B1 vacuum canister installed and couldn’t get the car to run and idle correctly, always thinking it was a carb issue. I install a B26 vacuum canister as specified by Duke and the car runs fantastic. For the last 10 years I always thought it was a carb issue. Now it starts easily cold or hot and I’ve been able to get the cold start fast idle dialed in at 2,200 rpm. On the street it drives excellent.

Regards,

James West

Sent from my iPhone

Reminds me of an old adage among Corvette owners: 90 percent of "fuel injection problems" are the ignition system. Yours is another example of how critically important it is to have a functionally correct VAC, but it is often overlooked.

Duke

[James G.]

Re: 65 365 really rough idle

Reminds me of an old adage among Corvette owners: 90 percent of "fuel injection problems" are the ignition system. Yours is another example of how critically important it is to have a functionally correct VAC, but it is often overlooked.

Duke

YES SIR, My first 65 FI car had distributor problem. Once resovled the dyno found 100 missing HP.

[Mark E.]

Re: 65 365 really rough idle

Did the engine run fine before your initial carburetor work to fix the leak?

If yes, the problem may be caused by whatever you changed.

[James W.]

Re: 65 365 really rough idle

Just as an FYI, Parts Geek has the B26 vacuum advance canister available, p/n 14078-05188558 for $12.18.

[Duke W.]

Re: 65 365 really rough idle

The 327/365 with the 30-30 cam needs an 8" B28 VAC... Airtex 4V1053, which is the last "brand" they are available in, but reports say they are getting tough to find.

Duke

[James W.]

Re: 65 365 really rough idle

Rock Auto only has 4 remaining of the 4V1053 vacuum advance canisters in stock.

[James W.]

[Duke W.]

Re: 65 365 really rough idle

Assuming OE equivalent cams a 15" B22 for the 327/300 manual trans and a 12" B26 for the L-78.

Duke

[James W.]

Re: 65 365 really rough idle

Duke,

Yes, both cars have the OEM camshafts. Thanks for the info.

James

[Richard G.]

Re: 65 365 really rough idle

I purchased one from Amazon on July 24, 2017.

Airtex Distributor Vacuum Advance 4V1053 Brand New

Currently unavailable is what Amazon's listing indicates.

[James W.]

Re: 65 365 really rough idle

Just ordered on Amazon a Borg Warner p/n V325 which is the number for a B22 distributor vacuum advance canister.

James