4.3 Litre 205HP 4V V6 specs?

[CamInc62]

I have just purchased a 1988 Thundercraft Temptation 265 with twin 4.3 litre, 205HP (high output) OMC V6's. It has the OMC (dogclutch) type sterndrives. My marine "guy" told me these motors take a R43T ACDelco Plug but the engines currently have R44T ACDelco plugs? He hasn't heard of these plugs, but we can get them and I am installing what was originally there. I do believe that they are a "hotter" heat range.

My questions is where can I find tune-up specs for these motors? I want spark plug gap, firing order, point gap/dwell, timing settings, etc. I have searched the forums to no avail. I am a newbie to this site and maybe I am overlooking something or not searching in the correct spot.

Any help would be greatly appreciated.
Great site with lots of information.

Thanks,
Craig

 

[Bondo]

Re: 4.3 Litre 205HP 4V V6 specs?

I have just purchased a 1988 Thundercraft Temptation 265 with twin 4.3 litre, 205HP (high output) OMC V6's. It has the OMC (dogclutch) type sterndrives. My marine "guy" told me these motors take a R43T ACDelco Plug but the engines currently have R44T ACDelco plugs? He hasn't heard of these plugs, but we can get them and I am installing what was originally there. I do believe that they are a "hotter" heat range.

My questions is where can I find tune-up specs for these motors? I want spark plug gap, firing order, point gap/dwell, timing settings, etc. I have searched the forums to no avail. I am a newbie to this site and maybe I am overlooking something or not searching in the correct spot.

Any help would be greatly appreciated.
Great site with lots of information.

Thanks,
Craig

Ayuh,.... Welcome Aboard,.... You should be usin' MR43T spark plugs,...

The "M" is Marine, which uses an alloy body, insteada steel, so's they don't rust in, 'n break upon removal,...

Spark plug gap oughta be .035",...

The points spec's, I donno, but somebody will be along that does,...

 

[Lou C]

Re: 4.3 Litre 205HP 4V V6 specs?

From my 1988 OMC owners/operators manual:
firing order 1-6-5-4-3-2
max rpm range (4bbl carb) 4400-4800
idle 500-600 rpm in fwd gear
ignition points: gap 0.018, dwell 39*+-2
timing, regular gas 1* BTDC
premium gas 6* BTDC
spark plugs AC MR43T gap 0.035
motor oil capacity 4.5 qts with filter
drive oil capacity 64 oz
thermostat 160*


look here for how to R+R the drive and how to properly change the drive gear oil
Articles & Instruction - Crowley Marine

Here for the tools that help adjusting the shift cable and the factory instructions including later service bulletins that give the finer points and more clear instructions than even the original factory manuals...I used the OE OMC tools on mine, followed these instructions and mine shifts great. Shift cable should have less than 2 lbs of drag measured with a fish scale. The drives should shift very easy into gear and out of gear. If not get them fixed or learn how.

Midnight Wolf Sales - OMC Tools

 

[Bondo]

Re: 4.3 Litre 205HP 4V V6 specs?

Thanks for the quick reply Bondo. You are correct they are MR series plugs which are the Marine and they are the MR44T, which again not sure why but my marine mechanic did find that series for those motors in a service manual. He just stated he has never came across that application.

Ayuh,.... My guess is, somebody at some time put the MR44T plugs in it,...

I'd still go back to the MR43T plugs, as that's what's Supposed to be there,...

If the 44s are hotter, you risk burnin' a hole in yer pistons with the "Hot" plugs,...

'n keep yer posts in yer thread,...
I generally ignore, 'n delete boat, 'n motor questions/ statements sent by pm,...