Yes, the 88 is the same as a 90hp, less injection and fancy voltage regulator... And although the basic block casting is the same, there are porting differences between the flat back models... Bubble back exhaust models have porting differences also. There are differences in the carb bodies also among the different horse power models, not just different jets.... These were great engines, simple, rugged, and easy to service...
Totally agree.. I have a 1989 88spl. Never rebuilt have about 1800 hrs. Compression is 90 psi on every cylinder. Runs perfect still .get my ski boat up to 37 mph. This outboard is truly a gem if you know how to take care of it..
The differences are actually two on the crossflows between the 88 SPL and 90/100/115hp for those with the VRO: 1. First as you mentioned, no VRO but pre-mix only. 2. The charging system is lower amps on the SPLs than the 90/100/110/115hp. (4 amps vs 9 amps on the non-SPL motors (90, 100, 110, 115 hp) That's because the SPL may come without the power trim & tilt. Balance does not matter on oversized piston kits IF they are manufacturered properly, they should be the same weight if they are std, 20, or 30 thous oversized. The main reason why people don't like to mix and match std with 30 thous oversized cylinder/pistons is the difficulty in managing the carb/jet changes required for it. Some two stroke motors (in general) may have cylinders that share the same jets on the same carb while others may not. It's up to the person asking to get it rebuilt to keep track of these details and know what needs to be done on the cylinders based on what the fuel system/carbs allow on the outboard. For example, lets say a single carb uses the same exact jets for feeding fuel/air to cylinders #3 and #4 and you increase the size by 1 jet size to compensate for the oversize. If #3 is 30 thous over and #4 is std size, then #4 will run like crap being too rich and #3 will run smooth/properly. In this example, you'd have to oversize both to 30 thousands because there's no way to make the fuel/air ratio different for the cylinders.
Good information. I had a 70 hp merc 3cyl rebuild I had 1 piston oversized 30 over and as you said the carbs were sharing different settings depending on jet size. This was my first rebuild out of many and I blew the engine because stupid me I didn't know any better and used different spark plugs than was required and I think the linkage on the carbs were not in sinc so it ran great for a few hrs then the top piston blew because of lack of lube and the spark plug I think made the cylinder run to hot. I was devastated I changed everything reeds bearings pistons cyl walls machined out.. but I learned a lot.i was 14 yrs old now I'm a serious rebuilder
I have a 1989 Johnson 110 hp The motor run everything smooth in neutral all the way but when I put in the lake run onto into 15 miles after the the motor die or stopped working I already do the carburetor repair ,do the same thing what do you recommend me to check or fix this motor??????
I have the same engine, ran it with no muffs or bucket and to find out that the kill switch was not operational, got to kill the engine by cutting the fuel supply,...it got I would say a bit hot,... I did a compression test to find out one cylinder was low in compression,... is the engine damaged? And what to do next,.... please help
Just got a hold of an 88SPL runs great I’ve changed the plugs and I am pretty sure it has power tilt and trim it’s just not hooked up ,, how would I check / verify / fix?
Check to see if it has the trim control box located between the 2 cylinder heads on the rear of the motor. Typically if it’s there the trim would be available. You can also look on the bracket for the trim unit. I would recommend changing the plugs, thermostats and fuel filters, gear oil, and clean the carburetors every season. I’d also recommend cleaning and greasing the prop shaft every season. Every 3 seasons do the water pump. Put good gas with stabilizer every fill up and you should be good to go
88 is same as a 90 without some thrills.... to make a 88/90 a 115 you need to do exhaust like you say , carbs and porting is a bit different too.... great motors.
Whats a motor like the 88 go for? i recently aquired a 93 Pontoon that has one on it. i dont know anything about it other than they said it doesnt run. I work on cars but when i under the hood of that, it looks pretty strange to me?
Excellent engine..i have one it's a rank..always wants to run.never let me down..easy to work on very simple.get a manual and you could rebuild one with no experience. But I highly recommend this engine.
I have 1989 Johnson 110 hp when I take to the lake the motor run into like 15 miles after the the motor die or stop running I really do that carburetor repaired and still do the same What do you recommend me to do to motor ?????
Have an 88spl and when I use the ear muffs I don’t get the flow of water from the line but when in the water it flow strong. My guess is they don’t supply sufficient water for cooling.
