carb question

[ill r]

Hello, all.

I have a "mutt" of an engine that started life as a Volvo AQ271C. (This is in an older style 24' Albemarle with I think a DP-A outdrive)

The previous owner put in a RECON long block, and replaced some of the bolt on stuff with Merc parts, I assume for cost reasons. I've been replacing with Volvo parts as things wear out. They sure do think a lot of their spare parts!

A little surfing around tells me the carb (Merc part # MCM 260/270 1347-8292) is a variety of Rochester Quadrajet, but I have been unable to find a cross reference that would get me to a Rochester model #. The carb seems to work fine other than one annoyance- no choke of any kind. Looks like the butterfly was wired open. Obviously, this makes for hard cold starting. So, the questions are: how to identify the carb? Suggestions for adding a choke (is there a standard part such that it doesn't matter exactly which carb I have?) Or for the time/money should I be looking at doing something altogether different?

Thanks,

-Bill R. (not "ill r" as I just noticed my user ID says :redface

 

[Gary H NC]

Re: carb question

Welcome to Iboats Bill,

Take a look at this site and see what carb matches up to the one you have.
A choke should be easy to come by.

http://www.flyingfishcarburetors.com/

 

[ill r]

Re: carb question

Thanks, Gary.

The Merc part number didn't match anything in their tables and the boat is not accessible to compare pictures right now, but I did send them an email with all the info I have available.

-Bill R.

 

[Bondo]

Re: carb question

Ayuh,... Hi Bill,+ Welcome Aboard...

Head on up to the Adults Only section,...
Up there you'll find many factory manuals for Merc.,+ Volvo...
Pick the SBC Merc manual, in it, it should have All kinds of Info on the Merc. Rochester spreadbore carbs used, as well as the Merc/ Weber/ Carter clone carbs they went to, at the demize of the rottenchesters...

 

[captmello]

Re: carb question

AQ271's came with a Holley oem.

Bondo - You're so predictable, never seen a Qjet ya liked.

Now you've got an aq260. Qjet was before volvo switched to the Holley.

 

[ill r]

Re: carb question

Aha!

The hunt is afoot, Watson!

Thanks to the very useful service bulletins, I see my carb is a Rochester 4MV # 17080561. A quick Google search reveals that the 170 verifies Rochester and the 80 would suggest year 1980, the last three digits everyone seems to interpret differently.

Should be easy enough to find a diagram and thus figure out what kind of choke it should have, but any opinions on switching to a new or remanned carb of a different make given the age of this? If I wanted for instance to go back to the OEM Holley, I would need to verify what the manifold is first?

 

[captmello]

Re: carb question

The Holleys were a square bore carb and the qjet is a spread bore. They would have different intake manifolds however there are adapter plates available. It should be easy to add an electric choke to your Qjet (Rochester). Take it to a carb shop and have it checked and see if they can add a choke. Or see about doing it yourself.

 

[ill r]

Re: carb question

If I can be assured of getting the right parts, no problem with putting it in myself. From what I remember, there isn't any of the linkage or anything past the butterfly left on the carb, so we'll see.

Thanks for the help and suggestions, all- this forum is a tremendous resource. The info in the several locked threads at the top alone will save the typical DIY'er many hours of time.

-Bill R.