We must be mistaken.
There are more than a few people on this forum and countless others that are using MC2100 and MC2150 carbs without any problems at all. It's just about the most comon swap on a AMC 258 i6 / 4.2l for more reasons than their cheap price. They're so simple to build and tune, a caveman could do it!
Unfortunately the tag was missing from my carb as well, so I have no eact application that my carb came on originally. All I know is I was able to match up a kit with the exact same gaskets from a 1971 Ford F100 with a 302. I never ran across anything in all my research on MC carbs that suggested that there were different models for auto or manual trannies. I'll have to take a look at my carb because I'm drawing a blank on how the passage is routed for the ported vaccum. I don't think it goes through any gasket mated surface, so that would eliminate the possibility of the wrong gasket being used that would block it.
That's exactly right. The HEI vaccum advance canister that for some reason looks like a wrench would fit on it is the adjustable one. From what I've seen, all the aftermarket HEIs come with them, including my super cheap ebay special.
When I posted earlier with the following, that was a quote from the web site that says anyone who puts an HEI in their AMC engine is doomed. You might notice the qualifier "Factory GM HEI" but the site says nothing about aftermarket HEIs or the fact that those adjustable vaccum advance canisters are a dime a dozen and will also fit the factory GM HEI. It's a very biased against HEI web site. Every other site I've found that slams the use of an HEI in an AMC just gets all of its info from that same site. I personally look for independent information to back something like that up, but people just keep regurgitating what they read. Tell that stuff to all the thousands of people running HEIs in AMC engines or to all the reputable companies that sell HEIs set up for the AMC. You get a few people that either didn't set their new distributor up with the correct gear, or failed to tune the new distributor to match their engine, and all of a sudden they're all a problem in some people's minds.
My 2100 is the same model as Rescue has. Vacuum advance is hooked to the left side of the carb looking from the Cj grill. Pcv valve is hooked to the port in the manifold directly under the carb. Never ran better.
They're so simple to build and tune, a caveman could do it!
I see no carb problem here. He pulled over, the engine was ideling, so there should not have been any vac. at the ported fitting. Right?On the way home today, I had a thought and a guess....keep in mind I don't know diddly about carbs/engines. I wondered if perhaps the distributor was failing to advance properly due to Limited vacuum. Well I pulled over and pulled the vacuum line to the distributor. It had very weak suction.
I felt a few of the vacuum ports on the carb (most are capped so I just uncapped them and tested them) and found one that had better vacuum. Plugged the distributor into that one. Drove off.....problem solved. No more knocking. Seems to run smooth and strong not matter how hard I am pushing it. Starts strong.
Cheers,
TrebleHook
The biggest danger on the internet is incorrect and incomplete information being shared around as if it's an absolute fact. That web site's claim or at the very least, attempt to give everyone the impression that you can't have an adjustable vaccum advance on an HEI is totally false. The only way to combat this false information is to put the truth out there with proof to back it up. But in a polite way.
