Trojan Boat Forum

Hi all,

seems like I need to tweak/upgrade my wires/cap/rotor, given my current lack of power and missing/rough idling. looking at timing, and figured might as well replace wires/cap/rotor.

phoned a few auto places, but they wanted the exact engine year. Any thoughts on how I would find this out??

Also firing order for this engine....my web research shows 2 different results.

I would go to the boat and get the numbers off the block, but thought if I could save a trip you experts might be able to help.


Cheers,
Aaron

trojandoc:

You'll need to know whether your engine has a Mercury Marine or Prestolite distributor before buying parts. Here's what my Mercruiser issued service manual says for all Model 233 (Ford 351 2V) Inboards:

Compression Ratio: 8 to 1
Point Gap: .016-.021
Point Dwell: 26-31 deg
Point Spring Tension: 17-21 Oz.
Spark Plug: (18MM) AC-C83T or Champion F-10
...................(14MM) Champion RBL-11Y (RV12YC)
Plug Gap: .030
Timing at Idle: 10 deg BTDC
Max RPM @ WOT: 3800-4200
Idle RPM (in gear): SN 4173767 & below - 550-600 RPM
..............................SN 4173768 & above - 650-700 RPM
Firing Order: L.H. Rotation 1-3-7-2-6-5-4-8
.....................R.H. Rotation 1-8-4-5-6-2-7-3
Oil Pressure @ 2000 RPM: 40-70 psi
Oil Pan Capacity w/Filter: Approx. 7QT

Mercruiser Part Nos. (Revised June 1976):
Mercury Marine Dist:
Cap: C-393-4988
Rotor: B-65864
Condensor: B-81-65851
Point Breaker Assm: B-64850
Coil: C-32193
Prestolite Dist:
Cap: B-392-6318
Rotor: B-392-6326
Condensor: B-392-6324
Point Breaker Assm: B-392-6325
Coil: B-32193
All:
Sparkplug Wire Lengths: Cyl #8: 38.5"
........................................Cyl #4: 37"
........................................Cyl #7: 34"
........................................Cyl #3: 31"
........................................Cyl #2 and #6: 28"
........................................Cyl #1 and #5: 24"
Fuel Filter (spin-on type): C-35-60494

...Other Part Nos., as well. Hope this helps.

They also used a Mallory dist, Unless your auto parts store sell marine parts you wont find the right parts ford parts won't fit ( other then plugs )

Also they used both 18mm and 14mm plugs (the ones Johnny listed are 18mm ) easy way to tell if a 13/16 plug socket fits its 18mm if a 5/8 fits its 14mm.

prowlersfish wrote:Also they used both 18mm and 14mm plugs (the ones Johnny listed are 18mm ) easy way to tell if a 13/16 plug socket fits its 18mm if a 5/8 fits its 14mm.

Prowler... I did list Merc's recommendation for both 18mm and 14mm plugs.

jon_e_quest wrote:

prowlersfish wrote:Also they used both 18mm and 14mm plugs (the ones Johnny listed are 18mm ) easy way to tell if a 13/16 plug socket fits its 18mm if a 5/8 fits its 14mm.

Prowler... I did list Merc's recommendation for both 18mm and 14mm plugs.

I must have over looked that sorry

Thanks jon-e-guest fantastic detail that I will take to my local marina--will stay away from car auto.

Cheers,
A