1969 Johnson 9.5

[lakelover]

This 69 Johnson 9.5 is an old timer that I'm planning to mess around with, was told a year or two ago by a dealer that compression was low, on its last legs, don't bother with it, etc. I have a feeling they just didn't want to be bothered with it. Water pump seems good, with a good healthy stream from the tell tale, I think the impeller was replaced two years ago and it has seen light use since then.<br /><br />Engine will start, but is hard to start, lots of mucking around with the slow speed adjustment and choke. Once started and it gets warmed up, WOT is very slow until the slow speed adjustment is leaned out, then goes pretty well on a light 14-footer, although it doesn't have the oomph it used to.<br /><br />I decarbed it using one can of Mercury's engine tuner and got lots of smoke, but didn't really notice a difference in performance. Should I do it again? I really don't know if it's ever been decarbed before. No black stuff came out, just lots of white smoke.<br /><br />I have a Seloc manual and just wonder if someone could point me in a starting direction for making it easier to start and maybe not having to fool with the low speed adjustment so much to get it a little faster at WOT?<br /><br />Thanks.

 

[rickdb1boat]

Re: 1969 Johnson 9.5

I would first re-check the compression and see if the dealer was correct or not. If it's OK, I would rebuild the carb and clean it out real well and give it a shot.. Of course, also use fresh gas and oil mix at 50:1 ratio. No amount of adjusting on the carb will make up for gummed up innerds in the carb. Let us know the compression readings are and we'll go from there.. Did it sit for along time without running??

 

[lakelover]

Re: 1969 Johnson 9.5

Typically it sits from September-June; each September I ran the gas out then fogged the cylinders. I don't have any way to check the compression, and probably won't be able to work on it until later this month; maybe I'll order a carb rebuild kit, grab my manual and go from there.<br /><br />Do you think further de-carbing would be of any help?

 

[rickdb1boat]

Re: 1969 Johnson 9.5

no

 

[lakelover]

Re: 1969 Johnson 9.5

I used the parts finder here on iboats and there is no carb. kit listed for this motor. Does it interchange with another one, or am I out of luck?

 

[wayne h]

Re: 1969 Johnson 9.5

compression gauges are very cheap if u dont wanna buy 1 u can rent 1 from the local auto store for a few bucks. u really need to know the compression of the motor before u start with a tune up. i have a few of these motors and a ton of parts for them they are great little motors and pretty easy to work on but there are a few little tricks to them that i have found only the factory service manuals will tell u. i have seen alot of these motors hit the trash pile because if bad trouble shooting even know they are oldies they are still worth there weight in gold when running right.everything is still avalable to tune her up. factory manuals can be found on ebay and also some hard to find parts

 

[lakelover]

Re: 1969 Johnson 9.5

Thanks rick and wayne for the info-do you know a good source for purchase of a basic gauge?

 

[wayne h]

Re: 1969 Johnson 9.5

just a basic gauge from the local auto store will be fine for what u are doing

 

[ezeke]

Re: 1969 Johnson 9.5

382048 is the part number for your carb kit. Any J/E dealer can get it for you. If you want to order one online try here: Carb Kit

 

[lakelover]

Re: 1969 Johnson 9.5

Terrific! You folks always have some good info. It may be a while before I can get to it, but I'll post back and let you know how it's going.

 

[lakelover]

Re: 1969 Johnson 9.5

Another question, since when I work on it I won't be near a computer. Assuming the compression readings are within 10% of each other on the two cylinders, what's the lowest limit they can be where I should still decide to pursue further work on the carb, etc.?

 

[lakelover]

Re: 1969 Johnson 9.5

^

 

[ezeke]

Re: 1969 Johnson 9.5

I have five that run real well at 70 to 80 PSI. Even use one with a long shaft for my kicker motor.<br /><br />Don't think that it is worth the money and time to tear them down as long as I get good performance. <br /><br />The biggest problems I've had with these motors are: 1. keeping the carbs clean; 2. cooling (the after market water pump impellers don't make it). <br /><br />I've had no real problem with carbon since I switched to synthetic oil. I use Champion J6J at .030 gap.<br /><br />If you put a fuel filter on your fuel line, you will be better off.

 

[lakelover]

Re: 1969 Johnson 9.5

Thanks all for the info, much appreciated!

 

[lakelover]

Re: 1969 Johnson 9.5

I'm planning to pick up a cheapo $25 compression gauge today. My plan is to check the motor at the dock with the motor on the boat hanging in the water. Any trouble with this plan? I've never used one before.

 

[lakelover]

Re: 1969 Johnson 9.5

I checked the compression and it was 60 top and 60 bottom. Then I added some 30w oil and rechecked and it went to 70 & 75. I gave the cylinders the seafoam soaking treatment and now it idles to a slower speed without stalling and runs smoother, but top end is still somwhat weak, although passable.<br /><br />One thing I noticed is that a lot of exhaust, and I mean a lot, is coming up from the lower unit into the powerhead area and I'm sure the carb's getting choked with exhaust. It runs a lot better with the cover off.<br /><br />Can the exhaust problem be remedied and how much of a job is it?<br /><br />Also, with such low compression, I'm wondering now if it would be worthwhile or not to get a carb kit for it.<br /><br />Any thoughts? Thanks.

 

[wayne h]

Re: 1969 Johnson 9.5

they are known for the exhaust donuts going bad in the mid section. alot of people cut a hole in the cowling right over the carb. i have about 5 cowls like this. this would not be my first choice in trying to fix the problem haha. if u dont have a manual get 1 for it try to find an original service manual ususally they are on ebay and go very cheap. the job is not really hard but it does take time. i have 6 of these motors 4 of them needed the donut. they are great motors and i think they are worth saving most of mine came from the scrap pile at local outboard shops.does it chock at all with the cowling off the motor or only when its on ? the exhaust donut is pretty cheap and can still be gotten at any omc dealer. becarfull and just take apart the carb and clean it check the float level make sure you take out the drain screw in the bottom of the bowl there there is jet in there and tends to collect alot of crap and plugs up. if u are carfull you might not need a kit for the carb. look at napa or your local dealer for parts they will have them or can order them alot of people dont know it but napa can get a ton of outboard parts. good luck and let me know how u make out. remember that is a good easy motor once you know the tricks

 

[McGR]

Re: 1969 Johnson 9.5

Wayne -<br /><br />Out of curiosity what is the donut you refer to? Are you talking about the rubber boot between the exhaust housing and the lower cowling?

 

[wayne h]

Re: 1969 Johnson 9.5

yes thats it

 

[lakelover]

Re: 1969 Johnson 9.5

Originally posted by wayne34609:<br />does it chock at all with the cowling off the motor or only when its on ?

wayne,<br />Not sure what you mean by this. It runs pretty well without the cowl on, smoother and faster, doesn't seem to labor as much. Probably will be a while before I do more on this engine. Thanks for the info, I'll post again when I have anything new.<br /><br />Also, I see that the recommended plug is J4J, mine has J4C. Any difference?