What is it???

[tourdriver1]

I have a 4 cyl Chrysler outboard. The model no on the unit says 757hb but!!!
Its 4 cyl,It came with 2 cowls 120 and 140 both fit. Is there an engine no somewhere on the block that will allow me to identify it. I am from New Zealand and info is hard to come by down here. Distributor ignition,Magnapower box 2 carbs. As i said its hard to get info in this country as there werent too many chryslers sent down under. Thanks in advance

 

[eurolarva]

Re: What is it???

757HB is from 1976 however that motor only has three cylinders not four. Also looks like it has a magna power ignition. If you have 4 cylinders the power head must have been replaced with a newer say 1983 90 HP. Around 1983 chrysler went from 3 cylinder to 4 cylinder on the 90 HP but not the 75 HP. Normally ID stamp is not on the power head so I am assuming the original powerhead was fried and it was later replaced

 

[tourdriver1]

Re: What is it???

So how can I find out what it actually is. there are some matching numbers on the baseplate of the carbs that i assume are model nos but probably only of the carbs. You are correct in that the model no plate is on the lower cowling so it would have been left if the powerhead was replaced but I need to know what the powerhead is.

 

[JoeCrow]

Re: What is it???

I had the same problem
The model and serial number on my midsection came back to an 85hp and I have a 4 cylinder, so I know it's a 125
On the block there should be a brass plate called a welsh or welch plug (not sure which) it has a number that will tell you what the block is
Problem is these motors (85 and 125) have all interchangeable parts
So the motor cover, lower end and midsection are meaningless

 

[eurolarva]

Re: What is it???

You can try chrysler crew. If you have the carb numbers they might have been introduced at a later time and could be valuable information. You can google mecruiser by mercury and look through their power head diagrams and see if you can find one to match.