Mercury 150HP front middle cowel cover piece missing help plz

[tawas23]

I just bought a 78 Hydra sport 17.8 bass boat that has a 150hp V6 Mercury on the rear and I cant find any info on year and I need a front middle cowel cover and dont know which one to buy as I cannot find anything on the serial number thats on the transom mount # 5130069 can anyone help me find a number for a front middle cowel piece as it has a 3 pce cowel 2 sides that come of individual and the front middle piece that I need to find .Can anyone help me with finding the front middle piece thanks in advance ..The engine cover is blue and think its a 1979 but not sure as I cant find any numbers that would match my search all the sites say cannot find??

 

[Chris1956]

Looks to be 1979. I assume you want this part 5399A3 which is the front cover. You will need to get one off e-bay or some used parts place as it is NLA from the OEM. The good news is that the piece from a 175HP or a 150HP motor likely will fit. The bad news is that Merc only made those clamshell cowlings for a few years, say 1978-1989 or so.

 

[tawas23]

thank you Chris1956 for your help I did find that one on ebay I really appreciate your help thanks again.Can you tell me if this is a good motor and is there any common issues with this year engines.I have not started it yet but going to later today.and why doesn't anything come up under the model number on the side of the mount 5130069..how can you see its a 1979??

 

[Chris1956]

Serial number indicates year. Try the model year guide on the maxrules website.

Your motor is a proven design, still in use today, or at least the block is. Changes were made to the carbs and ign systems.

Your displacement is likely 2.0L, which was changed to be 135HP, when the 150HP motor went to a 2.4L block. Some 150HP motors are 2.5L blocks, as well.

The concerning part about your motor is it likely has carb floats which are NLA. So treat them with care, whenever you service the carbs. Your motor may have fixed idle jets as well. So the carb is not adjustable, which is fine, provided she runs good. Again pay particular attention when servicing carbs so they are spotless and the float is set properly.

Other than that, enjoy. If you need to buy a new prop, you will need to pay attention the hub size of the current prop. You likely have the smaller hub (4-1/4"). Most newer V6 motors use the larger hub (4-3/4"). Both are widely avail, just get the right one....