Help ID my engine and carb

[mguidry629]

This is for the Chris Craft in my sig:

I don't have a Mercruiser stamp or tag anywhere on my engine, but I do have the #'s off the block. On the starboard side top of block in the rear above the starter is has 10243880. I believe this is a serial number or ID # of some sort?

The Rochester Q-Jet says 17059280 1785 W. All my research shows this came off of a big block Mercruiser. What does the 1785 W mean?

I knew the motor was not original to the boat, but was told it was a Mercruiser 5.7 260hp replacement installed in the late 90's, same as the original that was in the boat.

The alpha one outdrive serial is OB538800. I believe this is original to the boat.

I'm trying to ID the motor to see if this is a Mercruiser or if it is an Auto block that was rebuilt just for my own curiosity. And I was planning on rebuilding the carb, so I pulled the numbers off of it to order the parts. The motor runs great but the carb flooded last time out, I think the float got stuck. Tapped on it a few times and pinched the fuel lines and it went back to running good.

 

[achris]

Re: ID my engine and carb

Re: ID my engine and carb

I'm trying to ID the motor to see if this is a Mercruiser or if it is an Auto block that was rebuilt

Same thing. Mercruiser use GM engines. The same block is used for cars, trucks and marine engines. What makes the difference is what goes on/in the block once it's function has been decided...

The drive serial number is for a 1987, 1.50:1 Alpha One drive....

Chris.......

 

[mguidry629]

Re: ID my engine and carb

Re: ID my engine and carb

Ya I realize the blocks are the same, but I thought maybe I could find out if this block came from a dedicated mercruiser engine or if it was pulled out of an car/truck.

 

[mguidry629]

Re: Help ID my engine and carb

So it looks like ID'ing the motor is not going to happen....What about the carb? Did this carb originate on a big block? If so, how does that affect my air fuel ratio with it on a small block? Do I need to change jet size? It seems to be running good as is, but I'm going to rebuild it since it was sitting up for a few years and it flooded last time out.

 

[achris]

Re: Help ID my engine and carb

Post a photo of the carb. If the block was an original Mercruiser, then there should be a red aluminium ID plate on the block just above the starter motor. That will have the engine serial number on it...

Chris......

 

[Don S]

Re: Help ID my engine and carb

Here is a service bulletin with some ID numbers you might check on.

View attachment 02-08 GM Eng. Nos..pdf

According to service manual #9, that carb was used on the big blocks, but it was also used on the Tempest 300 engine that is a 350.

 

[mguidry629]

Re: Help ID my engine and carb



Thanks guys....Here's a picture of the carb....I have a rebuild kit on the way so I'm going to remove it this week and see what I find out when I get inside of it. I'm now pretty confident it is off of a big block but it's running good from idle to WOT, so I assume the A/F ratio is ok. Just seems like it would be running rich if it was built to feed 104 more cubic inches. Maybe my thought process is off base there. As far as the engine goes, I'll see if I can find the engine code and refer to the pdf Don posted. Looks like it should be in front of the starboard head above the water pump. Thanks for the help.

 

[achris]

Re: Help ID my engine and carb

Any chance of a photo of the complete carb? I have a sneaking suspicion that might be an automotive carb...

Chris......

 

[Don S]

Re: Help ID my engine and carb

Any chance of a photo of the complete carb? I have a sneaking suspicion that might be an automotive carb...

Chris......

The number shows it's a marine carb.

.

 

[achris]

Re: Help ID my engine and carb

The number shows it's a marine carb..

Cool.