Mercury 35hp needs to warm up before I can shift

[N62350]

I have a 1970 ( I think) 35hp Mercury with relatively low time. I started it today for the first time since I've had it, and I couldn't get it to shift into gear without it fully warmed up. Is this a choke problem or a gummed carb jet? Any thoughts/suggestions?

 

[Barnacle_Bill]

Re: Mercury 35hp needs to warm up before I can shift

Post the serial no and we can verify the year for you. Most motors need to warm up a little before use but it may just be idling to low. If the motor has been sitting for a long time without use, read this. http://forums.iboats.com/showthread.php?t=158086

 

[emckelvy]

Re: Mercury 35hp needs to warm up before I can shift

It may be as simple as too-lean idle mixture. Try adjusting the idle mixture screw 1/8 turn or so CCW (rich) and see if it gets better. For a more accurate adjustment, warm the motor in the water and adjust when idling in gear. Set the idle mixture on the rich side of the adjusment band as these motors have no accelerator pump and need to be set richer than you'd think.

If that doesn't help, you'll probably want to do as the O.P. said & service the carb.

HTH........ed

 

[N62350]

Re: Mercury 35hp needs to warm up before I can shift

The motor hasn't been run in a year, so I don't think it could get that gummed up. ( Although with 2-cycle gas, anything is possible) I agree that all engines need to be warmed, but not for 8-10 minutes. I will try to richen the mixture a tad, but before I mess around any more I am going to service the carb. I will get the serial number tommorrow since I really have no idea how old the motor is.

 

[N62350]

Re: Mercury 35hp needs to warm up before I can shift

I am not 100% sure this is the engine serial number. It is a small plate about 2inches long. It reads: Kiekhafer Mercury Serial # 1433651.

 

[N62350]

Re: Mercury 35hp needs to warm up before I can shift

Can anybody identify the year of my motor by the number I posted?

 

[emckelvy]

Re: Mercury 35hp needs to warm up before I can shift

Purty Old! My book goes back to '65 and the starting ser # for the 350 model was 1755799.

Your motor probably is something like a '63. A real classic!!

Silly question, 2 cylinders or 4?

Does it look like this 2-cyl:

http://www.eastcoastmarineservice.com/1963merc350.htm

Or more like this 4-cyl:

http://www.eastcoastmarineservice.com/1961merc350.htm

 

[N62350]

Re: Mercury 35hp needs to warm up before I can shift

My motor is a 2 cylinder model. It looks newer than the one in the link you posted. Not as much chrome. I found this plate in the bottom of the boat. I wonder if it is off of another engine? Not likely but just a possibility.

 

[emckelvy]

Re: Mercury 35hp needs to warm up before I can shift

Well, there's always a '67 like this:

http://www.eastcoastmarineservice.com/196769merc350.htm

It's possible you may have a Mix-n-Match motor, hard to say without a pic.

 

[N62350]

Re: Mercury 35hp needs to warm up before I can shift

Now my motor looks EXACTLY like the 1967-69 models, but the srial numbers don't match. What exactly do you mean by mix n' match motors? Also, what spark plugs should I run? I currently have old J-6-J plugs in there that need replacement. Will try to post picture but I'm not promising anything.

 

[Barnacle_Bill]

Re: Mercury 35hp needs to warm up before I can shift

Way back when they recommended using Champion L4J (now L82C) plugs gapped to .030

 

[emckelvy]

Re: Mercury 35hp needs to warm up before I can shift

A lot of the parts on these old motors are interchangeable, it's entirely possible for someone to have swapped powerhead, changed cowlings, etc to give it a newer look. It's also conceivable that the missing ser # plate is unrelated to the plate you found loose in the bowels of the boat.

'67-'69 350's took a longer-reach (1/2") L4J plug. Earlier models used a J6J, which is a 3/8" reach plug.

You definitely need to make sure the correct plug is in there; a short-reach plug in a longer-reach motor won't run right, and long-reach plug in a short-reach motor could possibly hit the piston.

You can easily measure the depth of the spark plug holes in the block, just pull the spark plug and measure from the machined surface of the block to the end of the threads. The diff between 3/8" and 1/2" is very evident.

Updated #'s for the L4J and J6J are L4C or L77JC4, and J6C.

This could be a very good way to narrow down the year of your motor, if you have 1/2" reach plugs it has to be at least a '67 which would make it very likely that your motor has its original cowlings.