timing question

[travissowell]

Hello all, first time on this forum.. well i bought a new to me bass boat with a 1990 175 evinrude that was rnnin badly. I ran a comprssion check and all were pretty good 100,95,95,100,100,65.... the 65 hole had water on the plug so i changed a head gasket, it was clearly blown. now that hole is at 100 So while i was messing with the motor I notice the throttle was only opening the carbs 1/2 way so fixed that. I also notice the wot timing screw was screwed almost all the way in.. I searched every where for the wot timing and came to the conclusion to set it off the starter at 20deg.. I went to the local omc parts/repair house and the mechanic there told me to DO NOT TRUST the timing off the starter method. He told me to run the motor at 3800 rpm and set it at 28deg. while making sure the timing rod is pulling to the stop on its own. so my long winded question is, is 28deg were it needs to be??
I have been told two different things now 20 and 28.. I got the 20 off this forum. AND yes I have ordered a book but i am plannin to go and run it tomorrow and dont want to melt any piston ya know. Thanks guys

 

[travissowell]

Re: timing question

whats going on here? 105 people viewing this site and no one knows

 

[travissowell]

Re: timing question

bump bump

 

[clanton]

Re: timing question

Tomorrow I will post timing specs.

 

[travissowell]

Re: timing question

thank you.

 

[clanton]

Re: timing question

This is a V6 crossflow engine. The max timing is set at 32+- 1 degree BTDC, at 5000 rpms. You can use your mechanic or Joe Reeves method, but the final check should be at 5000 rpms. As the rpms increase the stator voltage increases and will move the timming 2-6 degrees, most of the time close to 4 degrees. The reason for the final check at 5000 rpms. DO NOT run engine with out a load.

 

[emdsapmgr]

Re: timing question

The 1990 factory service manual requires the maximum timing for a 175 to be set at 28 degrees, plus or minus one degree set at 5000 rpm in forward gear. Once you time it for cyl #1, repeat the step for cylinder #2. Select the cylinder with the highest degree timing and adjust that one to 28 degrees.

 

[travissowell]

Re: timing question

took the beast out today and wow all the work i did paid off. i went ahead and timed it like the mechanic told me at 28deg. what is the max wot rpm for this motor? it has a 14 1/2" 19 pitch prop on it now. the 175 is mounted on a stratos 17'9" bass boat. i have a 22 pith prop that i could put on it.

 

[clanton]

Re: timing question

My mistake 28 degrees it is.

 

[travissowell]

Re: timing question

i guess i am glad i listened to the mechanic and not you. i might have been lloking for a new motor

thanks again

 

[emdsapmgr]

Re: timing question

This engine is prop rated at 175 hp at 5250. It is an underrated engine and actually makes more like 192 at the prop. This is a high port engine rated by the factory to run normally between 4750 and 5750 rpm. Current thinking is to run in the upper end of this "normal" operating range. I would prop it to run at least 5750. That engine will breath well and make good hp up to 6000. You don't want to lug the engine. There is a rev limiter in the factory power pack set at 5800, so you won't harm the engine.

 

[travissowell]

Re: timing question

thanks for the advise guys.. i put a 22 pitch on it and it seemed to get out of the water faster and had gobs of power once on plane. i had a 19 pitch on it yesterday. i dont quite understand how a 22 would perform better on low end than a 19 but it seemed to.