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ctjahn
06-11-2012, 09:01 AM
iPhone signal is weak to search forums.

What should the timing be on a 78 MC 351 elect ign?

I thought I set it to 10. It's loosing power after 3000 rpm and over 30 mph. (after elect ign and timing adjustment

Saw two MCs up on Nokomis flow age yesterday: BF 200 and a Mia 80s S&S


Cj

thatsmrmastercraft
06-11-2012, 09:19 AM
10 should be good as long as it doesn't ping. Have you checked if your secondaries are opening? Could be the weights in the dist aren't giving you full advance.

TRBenj
06-11-2012, 10:32 AM
Let me guess, Pertronix? If so, throw it in the garbage! Ive seen it happen before (several times). Going back to points fixes the issue.

10 initial is fine.

ctjahn
06-11-2012, 06:05 PM
Thinking back I think I timed it looking at the side rather than top down... There must be a reason it is falling on its face at the top end....will try retiming looking down from the top and give it a go... We don't NEED to go faster than 32 but.... It's not right.

Cj

TRBenj
06-12-2012, 08:56 AM
Thinking back I think I timed it looking at the side rather than top down...
:confused::confused:

ctjahn
06-14-2012, 10:17 AM
:confused::confused:

Becayse it is a pointer and the timing marks are viewable from multiple perspectives; I wonder if it matters if you view the marks from the top or at a 45 degree angle; which in fact will affect the actual timing when using an old timing light... Make more sense?

thatsmrmastercraft
06-14-2012, 10:19 AM
Becayse it is a pointer and the timing marks are viewable from multiple perspectives; I wonder if it matters if you view the marks from the top or at a 45 degree angle; which in fact will affect the actual timing when using an old timing light... Make more sense?

I'm thinking you could be off by as much as 5 degrees.

TRBenj
06-14-2012, 11:23 AM
No way. The pointer and balancer arent far enough apart to be able to see any difference in timing readings when viewed from different angles.

You didnt answer my question- did you install a Pertronix EI kit? If that corresponds to your reduced performance, it wouldnt be the first (or second) time Ive seen that happen.

thatsmrmastercraft
06-14-2012, 12:27 PM
No way. The pointer and balancer arent far enough apart to be able to see any difference in timing readings when viewed from different angles.

You didnt answer my question- did you install a Pertronix EI kit? If that corresponds to your reduced performance, it wouldnt be the first (or second) time Ive seen that happen.

Using my non-scientific measuring capabilities available on my desk (ruler, tape measure and a paperclip) I calculate that if the timing pointer is 1/4" from the damper pulley, and you view from a 45 degree angle to the timing mark, what you see is approximately 5/16" as apposed from viewing from directly above. Without going out to the boat to measure the timing marks, I think my estimate is pretty close on 5 degrees.

TRBenj
06-14-2012, 01:05 PM
IIRC, the pointer is closer than 1/4". I dont think the pointer/balancer can be viewed from a full 45 degree range either. Even if that is the case, having the timing off by 5 degrees would not cause the boat to degrade in performance to the tune of almost 1500rpm.

thatsmrmastercraft
06-14-2012, 01:43 PM
IIRC, the pointer is closer than 1/4". I dont think the pointer/balancer can be viewed from a full 45 degree range either. Even if that is the case, having the timing off by 5 degrees would not cause the boat to degrade in performance to the tune of almost 1500rpm.

I will agree with you on that point. Not really sure how it would run at 0 advance or less. Sure wouldn't have much to it. Could throw the points back in to see if it comes back to life. Most likely caused by something ctjahn did during the EI installation.

I would confirm the timing is set properly
Double check wiring connections with the instructions. Which EI are you using?
Confirm firing order is correct.
Confirm all plug wire and coil wire connections are good.
Confirm choke is open.

1redTA
06-14-2012, 03:28 PM
I just went thru the timing game on mine yesterday. It does vary a cOuple of degrees on the angle viewed. Holy parallax batman

TRBenj
06-14-2012, 03:44 PM
Not really sure how it would run at 0 advance or less. Sure wouldn't have much to it.
I can tell you- not good! I learned that the first time I set the timing on my '71 Correct Craft... which has a standard rotation balancer on a reverse rotation engine. Runs like crap with initial set to 10 deg ATDC.

Most likely caused by something ctjahn did during the EI installation.

Agreed.

thatsmrmastercraft
06-14-2012, 03:47 PM
[QUOTE=TRBenj;849019]I can tell you- not good! I learned that the first time I set the timing on my '71 Correct Craft... which has a standard rotation balancer on a reverse rotation engine. Runs like crap with initial set to 10 deg ATDC. QUOTE]

There are two ways to learn........:rolleyes::D

Philscbx
06-14-2012, 10:31 PM
You can easily tell moving it retarded anywhere near 0 or ATDC, it degrades instantly.
Firing after the piston is on the way down - just killed the whole process.

It can be done by ear just as well under load, by backing off the moment ping starts in advancing it.
Now see where the light hits after. Now it's tuned to the fuel used. Timing is 6 BTDC.
Granted if carb is 100%.

ctjahn
06-15-2012, 08:07 AM
IIRC, the pointer is closer than 1/4". I dont think the pointer/balancer can be viewed from a full 45 degree range either. Even if that is the case, having the timing off by 5 degrees would not cause the boat to degrade in performance to the tune of almost 1500rpm.

Yup. Pertronix installed. Still on vacation. Will re time it when I get home Saturday...

ctjahn
06-17-2012, 05:15 PM
Yup. Pertronix installed. Still on vacation. Will re time it when I get home Saturday...


Ok, re-timed it this morning... 6 Degrees looking top down. Sounded great in the driveway but as soon as I get it in the water at full song it falls off at 30 MPH. Next up is the plugs, wires, and cap... (which I dont think will make a diff but worth a shot before going back to points.)

What is the gap again? (with Electronic? 32?)

Cj

liledgy
06-17-2012, 08:45 PM
Did u replace the coil when u put the petronix in? If u did, put your original coil back in. I was sold a faulty coil and couldn't get the boat to run right. Finally narrowed it down to the new coil.

ctjahn
06-17-2012, 09:09 PM
Did u replace the coil when u put the petronix in? If u did, put your original coil back in. I was sold a faulty coil and couldn't get the boat to run right. Finally narrowed it down to the new coil.

Yes I did. I replaced it with the Pertronix Coil. Would that cause it to run fine except over 30 MPH or fall off with power around 3000 RPM?

cj

thatsmrmastercraft
06-18-2012, 10:43 AM
Yes I did. I replaced it with the Pertronix Coil. Would that cause it to run fine except over 30 MPH or fall off with power around 3000 RPM?

cj

A bad coil could do that. They usually either work or don't, but it is possible.

Philscbx
06-18-2012, 10:48 AM
Starting to sound fuel related - starving.

Has the system been checked - for flow/filter inspection test.

If it has inline filter - remove - tap the inlet side on clean paper towel to see if rust/dirt comes out.

thatsmrmastercraft
06-18-2012, 11:00 AM
Flat spot at 3000 rpm can be a bad secondary diaphragm not allowing the secondaries to kick in.

Philscbx
06-18-2012, 11:03 AM
Good idea with secondaries

ctjahn
06-18-2012, 11:13 AM
Ok, I will check it out but this didnt happen until the pertronix.

thatsmrmastercraft
06-18-2012, 11:30 AM
Ok, I will check it out but this didnt happen until the pertronix.

Most likely still dealing with effects from your work. I really don't believe in coincidences, but I guess they do happen once in a while.

TRBenj
06-18-2012, 01:04 PM
The secondary circuit on a 4160 is both RPM and load dependent (I believe venturi vacuum). I have never seen secondaries attempt to come in as low as 3,000 rpm on boats of this size. Always in the 3500-4k range. If it were a fuel supply issue, it would act as if it were running out of gas at sustained higher rpm's (when the bowls got low).

$5 says its a junk Pertronix kit.

liledgy
06-18-2012, 01:30 PM
Your symptoms are very similar to what I went thru, putting the original coil back on solved it. The petronix did fail the following year though, went back to points. This was on my previous boat. My 85 has a Petronix too and I'm keeping my fingers crossed.

ctjahn
06-20-2012, 01:24 PM
Subject: RE: Product Support Question/Issue

Try moving the adapter plate to the other rotation (from C to CC or CC to
C).

PerTronix Tech.

Really? Would it run if it were backwards??

thatsmrmastercraft
06-20-2012, 01:52 PM
Really? Would it run if it were backwards??

The timing being off 180 degrees wouldn't be an issue.

TRBenj
06-20-2012, 03:02 PM
The timing being off 180 degrees wouldn't be an issue.
Huh??

ctjahn
06-24-2012, 09:58 AM
Long story short before I rotated the Pertron, I wanted to check the distrib.

It appears one of the springs is missing... Is there a source for a spring on a distributor????? I suspect it is has specific tension and etc so I cant buy one just off the shelf at the hardware store?

Still not sure if this would cause the issue. And it would be a heck of a coincience that it broke and/or disappeared around the same time as the pertron was installed.

cj

1redTA
06-24-2012, 11:13 AM
I am interested as well, of the two springs,on mine, one is very small and attached to the pins with tension on the spring however, the big one is resting over the pins with no tension just voer the pins. Worst of all I get 24* at 4000rpm anyone no what the timing should be at that speed?

ctjahn
06-24-2012, 11:58 AM
I contacted skidim and others for advise on where to source it out... My next step is buy one from a 1978 ford from a junkyard. (whole distrib)... Will let you know what I find out.

cj

liledgy
06-24-2012, 12:28 PM
Did you swap out your coil yet?

ctjahn
06-24-2012, 02:00 PM
I am interested as well, of the two springs,on mine, one is very small and attached to the pins with tension on the spring however, the big one is resting over the pins with no tension just voer the pins. Worst of all I get 24* at 4000rpm anyone no what the timing should be at that speed?

Skidim got back to me. One is supposed to be big the other one is supposed to be small. They used to sell replacement kits years ago but dont offer it any more. No one else was able to provide a set. I did pickup a set of springs for a GM distrib and may give em a try if nothing else turns up.

cj

ctjahn
06-24-2012, 02:05 PM
Did you swap out your coil yet?

Not yet. The springs I am talking about affect the timing as the speed/RPM increases. So one would assume this isnt helping things. I dont live on the lake so testing is an ordeal. I am going to try the spring first, retime again, then the coil (I guess I could put the old one back in), and finally put the pertron to CW instead of CCW like they said (but I doubt this will even work?)

ctjahn
06-24-2012, 03:59 PM
Got a spring kit from MR Gasket. Installed one silver spring (max stiff) and one black spring (min stiff). Will time it again next weekend on the fake lake (Its sleeping in the garage and as I suspect that the timing is off because the old remaining spring was doing nothing. And I suspect it advaced itself to max when at idle.)

cj

ctjahn
06-30-2012, 05:49 PM
Great day on the lake! Last weekend Tuned up with new cap, rotor, plugs, (Gapped to .040 with Pertron)...and plug wires. Long story short....Issue resolved (not that it was that big of a deal because we didnt use 30-40mph for skiing but... it still bothered me that it wasnt right)

The springs in distributor were completely shot. One was gone, the other one rusted and crusty. Not really doing much. So when I adjusted the timing the distributor was at full advanced (nothing was holding it back). I talked to a boat mechanic and he verified that he thought that the springs were the source of issue)

On a guess (Since no one makes a spring kit any more); I got this from Tims (the local auto parts store) and gave it a a go: Mr. Gasket 929G - Mr. Gasket Advance Curve Kits (RACEONLY for GM Motors). I guessed again and used the lightest spring (Black) and the medium spring (Silver) - based upon TT feedback. Tested on the fake lake in the driveway and the timing advanced to 28/29 degrees at 4000 rpm. (Boat mechanic said it would be nice to see about 24-30 @ 4000. (Might switch to the heaviest gold spring instead of silver)

Ok, so it advances now... the real test was to do it under load. Took it out @10am. It ran perfect though the rev band. Power across the board. Boat runs and sounds better than ever! 39mph @ 4000 RPM. (I think thats on a 13x13 prop). Great out of the hole. Great top end. Kick a$$

Went to launch out and I had my own little 1.5 hour wait of boat lauch bloopers... (Ugh) but a great day on the lake and great weather while watching the drama made it ok. (although I think we cooked while waiting)

For those who can use this in the future, please note the Mr Gasket 929G part number... (only $5 -10.00; a heck of a lot cheaper than a distributor) Hope this can help out other folks as the TT group has been a great help to me.

Cj

TRBenj
07-02-2012, 09:02 AM
the timing advanced to 28/29 degrees at 4000 rpm. (Boat mechanic said it would be nice to see about 24-30 @ 4000. (Might switch to the heaviest gold spring instead of silver)

39mph @ 4000 RPM. (I think thats on a 13x13 prop).
28-29 degrees at 4000 is way too low, and way too late. You should see full advance by 3000 rpm, and ideally you'd be getting 35-36 degrees of total. If you recurve the distributor to achieve that, you will notice a huge improvement in low-midrange acceleration, and will likely find the 400rpm and 4mph that youre missing.

ctjahn
07-02-2012, 09:26 AM
28-29 degrees at 4000 is way too low, and way too late. You should see full advance by 3000 rpm, and ideally you'd be getting 35-36 degrees of total. If you recurve the distributor to achieve that, you will notice a huge improvement in low-midrange acceleration, and will likely find the 400rpm and 4mph that youre missing.

Sorry for the confusion... It maxed out at 28-30 degrees... Where it hit was tough to say (holding the timing light foot on the throttle, while trying to monitor, and not piss of the neighbors at 8am on a saturday); I just know it maxed at 28-30 or so at 4k.

Hmmm, since I am running the lightest spring and the medium heaviest spring; I could try to remove the light spring and just run on one? It does kick out of the hole quite well tho. (and after getting it running well, I would hate to break it now that it works!)

EDIT: In the garage this morning for work I did notice that the prop was 13x14LH....

cj

ctjahn
07-28-2012, 08:21 AM
Opened up the old girl last weekend and hit 44 on a chop (less fuel). Not too shabby for an old boat with an old motor....

cj

thatsmrmastercraft
07-29-2012, 12:17 PM
Opened up the old girl last weekend and hit 44 on a chop (less fuel). Not too shabby for an old boat with an old motor....

cj

.....................nice :toast:

ctjahn
08-25-2012, 09:52 PM
The girl got a workout this last week... but is jumpin out of the hole a bit slow (new driver so I dont know if it was driver related or mechanical)

Or 50/50. Thoughts on spring changes?

cj

ctjahn
09-02-2012, 04:30 PM
28-29 degrees at 4000 is way too low, and way too late. You should see full advance by 3000 rpm, and ideally you'd be getting 35-36 degrees of total. If you recurve the distributor to achieve that, you will notice a huge improvement in low-midrange acceleration, and will likely find the 400rpm and 4mph that youre missing.

I am going to change the springs again in hopes to get a better pop out of the hole. (and maybe have the carb rebuilt this winter);

Maybe going with a light and a medium (I think - cant remember) that I have one heavy one light. Will try to check it out next weekend....

Summer is coming to an end. :(

cj

j.mccreight@hotmail.com
09-02-2012, 06:28 PM
I am going to change the springs again in hopes to get a better pop out of the hole. (and maybe have the carb rebuilt this winter);

Maybe going with a light and a medium (I think - cant remember) that I have one heavy one light. Will try to check it out next weekend....

Summer is coming to an end. :(

cj

FYI, if you call prestolite 1-216-688-8300 and talk to their techline you can order reman distributors from them, send in your unit with $125 plus shipping and in 10-14 days you get a new reman in the mail with the proper mechanical advance built in. I recently called them for your very problem.

ctjahn
09-07-2012, 10:55 AM
FYI, if you call prestolite 1-216-688-8300 and talk to their techline you can order reman distributors from them, send in your unit with $125 plus shipping and in 10-14 days you get a new reman in the mail with the proper mechanical advance built in. I recently called them for your very problem.

My lake time is limited and rather than screwing around with springs to get a better hole-shot, i figured lets do it right and get it done... I called and it appears the guy had no clue what I was talking about.... :confused:. So. I submitted a request online.

Regardless I need to winterize the boat first as I dont want to end up in a situation where it freezes because I didnt have the replacement distrib to run the anti-freeze though it.

ctjahn
09-20-2012, 08:33 AM
FYI, if you call prestolite 1-216-688-8300 and talk to their techline you can order reman distributors from them, send in your unit with $125 plus shipping and in 10-14 days you get a new reman in the mail with the proper mechanical advance built in. I recently called them for your very problem.

Thx J.McCreight.

I toyed with more testing and adjusting the springs but finally decided to send it off. Lake time is extreemly limited and I didnt want to spend my time goofing around with springs and timing on the lake when there was little chance of getting it right.

Winterized the boat last weekend; yanked the distributor and sent it off to Prestolite. Arrived there yesterday. We will see how it goes.

(I did make a special request to retain or at the very least keep the Pertronix).

Cj

thatsmrmastercraft
09-20-2012, 09:11 AM
Thx J.McCreight.

I toyed with more testing and adjusting the springs but finally decided to send it off. Lake time is extreemly limited and I didnt want to spend my time goofing around with springs and timing on the lake when there was little chance of getting it right.

Winterized the boat last weekend; yanked the distributor and sent it off to Prestolite. Arrived there yesterday. We will see how it goes.

(I did make a special request to retain or at the very least keep the Pertronix).

Cj

Sounds like a good choice. Let us know how it works out. Might consider having them go through mine over the winter months just to prevent future issues.

dpcsar
09-20-2012, 02:08 PM
Good post to read! I have a similar problem with my '89 Prostar. It will not go over 4000 rpm. Completely new rebuilt engine. The distributor is the last old part. Points were replaced this year just to get the new rebuild running to 4000. I decided to get a completely new pertronix distributor and coil. I think that my springs are bad and didn't want to mess with the thing. I am hoping for the best and will time and test it this weekend.

If all goes well, I will have a distributor that someone can send to pertronix to rebuild. ;)

j.mccreight@hotmail.com
09-20-2012, 03:43 PM
ctjahn,
just noticed you have 13x14 prop, here is my insight,
89 351w 250hp, pre HCI swap, 4400rpm@43.5 mph with 29*@3000rpm with 13x13 4 blade.
Post HCI, 4800rpm@44.5mph with 29*@3000rpm 13x13 4 blade, massive torque but not much more top mph.
Had prop repitched 13x14 4 blade 4300rpm@45.5mph with 36*@3200rpm, this "new" distributor installed at the same time as renewed prop. Definatly lost some hole shot, low end torque with the 13x14 4 blade but picked up another mph with less wot rpm's.
I should have done the distributor at a different time as the prop to get an accurate comparison. Although my boat is a little heavier than yours the timing numbers should be similiar.
In the end I don't think the distributor added anything to performance in my case, but my original distributor was not missing parts and not corroded and was advancing smoothly to 29*@3000rpm.
I am going to put my original 13x13 3 blade prop back on and see what happens.
So with a stock 351w with a 13x14 prop I'm going to say approx. 4000rpm is probably all your going to get even if the timing is spot on.
My thoughts are to replace the distributor (which in your case is a giving since yours is fubared) making sure initial 6-10* and advance 34-36* setting are set properly and get a 13x13 prop to get your low end torque back.

ctjahn
09-25-2012, 09:10 AM
ctjahn,
just noticed you have 13x14 prop, here is my insight,
89 351w 250hp, pre HCI swap, 4400rpm@43.5 mph with 29*@3000rpm with 13x13 4 blade.
Post HCI, 4800rpm@44.5mph with 29*@3000rpm 13x13 4 blade, massive torque but not much more top mph.
Had prop repitched 13x14 4 blade 4300rpm@45.5mph with 36*@3200rpm, this "new" distributor installed at the same time as renewed prop. Definatly lost some hole shot, low end torque with the 13x14 4 blade but picked up another mph with less wot rpm's.
I should have done the distributor at a different time as the prop to get an accurate comparison. Although my boat is a little heavier than yours the timing numbers should be similiar.
In the end I don't think the distributor added anything to performance in my case, but my original distributor was not missing parts and not corroded and was advancing smoothly to 29*@3000rpm.
I am going to put my original 13x13 3 blade prop back on and see what happens.
So with a stock 351w with a 13x14 prop I'm going to say approx. 4000rpm is probably all your going to get even if the timing is spot on.
My thoughts are to replace the distributor (which in your case is a giving since yours is fubared) making sure initial 6-10* and advance 34-36* setting are set properly and get a 13x13 prop to get your low end torque back.

Any news on this (prob change?)? My boat seems to drag me(doesnt pop out of the hole) but I have about 50% probability that it was the driver (according to my wife who was watching)...

Cj

ctjahn
09-25-2012, 09:19 AM
My experience from Prestolite Repair. (To date)


I called Prestolite and opened up a ticket a month or so ago (Guestimate) to better understand the return process and where to send it. SHIP DATE: Monday, September 17, 2012, DELIVERY DATE:
Wed 19 Sep 2012 10:51 AM, Phone call 9/25/12 @ 8:13 AM. (about status and how they are proceeding.)


IN SHORT: They are going to send me a reman Malory unit (they said they dont have the materials or parts to reman mine), AND send back my Pertonix and associated stuff from the electronic conversion ALL for $75.00 plus shipping (including reman unit).


I did ask if I could use the same cap, which is still on the motor with the wires (they said yes but I am suspect.)


Will report back when I get it.

Cj

thatsmrmastercraft
09-25-2012, 09:47 AM
My experience from Prestolite Repair. (To date)


I called Prestolite and opened up a ticket a month or so ago (Guestimate) to better understand the return process and where to send it. SHIP DATE: Monday, September 17, 2012, DELIVERY DATE:
Wed 19 Sep 2012 10:51 AM, Phone call 9/25/12 @ 8:13 AM. (about status and how they are proceeding.)


IN SHORT: They are going to send me a reman Malory unit (they said they dont have the materials or parts to reman mine), AND send back my Pertonix and associated stuff from the electronic conversion ALL for $75.00 plus shipping (including reman unit).


I did ask if I could use the same cap, which is still on the motor with the wires (they said yes but I am suspect.)


Will report back when I get it.

Cj

Doesn't sound bad. Factory re-manufactured parts can be a great deal.

j.mccreight@hotmail.com
09-25-2012, 10:52 AM
Any news on this (prob change?)? My boat seems to drag me(doesnt pop out of the hole) but I have about 50% probability that it was the driver (according to my wife who was watching)...

Cj

This past weekend reinstalled original 13x13 3blade and most of the torque of the 13x13 4blade returned: 4500rpm @ 46mph picked up 200rpm and ~.5mph over 13x14 4blade.
Overall happier with the torque from the 13x13 either 3blade or 4blade versus the 13x14 4blade.
I am either going to repitch the 13x14 4blade back to 13x13 4blade (known performance) or replace with the Acme 541 CNC 13x12 3blade (unknown performance) on a recommendation.
If I had to rank torque performance,
#1 13x13 4blade
#2 13x13 3blade
#3 13x14 4blade

thatsmrmastercraft
09-25-2012, 10:55 AM
This past weekend reinstalled original 13x13 3blade and most of the torque of the 13x13 4blade returned: 4500rpm @ 46mph picked up 200rpm and ~.5mph over 13x14 4blade.
Overall happier with the torque from the 13x13 either 3blade or 4blade versus the 13x14 4blade.
I am either going to repitch the 13x14 4blade back to 13x13 4blade (known performance) or replace with the Acme 541 CNC 13x12 3blade (unknown performance) on a recommendation.
If I had to rank torque performance,
#1 13x13 4blade
#2 13x13 3blade
#3 13x14 4blade

Great info. New prop in the works for me for next year and this certainly helps. :toast:

j.mccreight@hotmail.com
09-25-2012, 11:08 AM
Great info. New prop in the works for me for next year and this certainly helps. :toast:

I don't mind being the guinea pig it just gets expensive:(

13x13 4 blade 4800rpm@44.5mph #1 for torque #3 for mph
13x14 4 blade 4300rpm@45.5mph #3 for torque #2 for mph
13x13 3 blade 4500rpm@46mph #2 for torque #1 for mph

anybody have an Acme 541 i can try out:D

TRBenj
09-25-2012, 03:14 PM
That 13x13 4-blade is acting more like a conventional 13x12 based on those WOT RPM's vs. speed numbers. Its not surprising it came out of the hole the best. Numbers look consistent on the 13x14 and 13x13.

Assuming these are all older hand finished props with some run time on them, I wouldnt spend a dime "tuning" them. Id be skeptical that a repitched prop could ever provide optimal performance. Personally, Id keep the 3-blade 13x13 around as a back up and sell the other 2 for as much as you can ($50-100/ea) and put the money towards a 541. After you try one, you'll despise the thought of running anything else.

j.mccreight@hotmail.com
09-25-2012, 06:36 PM
That 13x13 4-blade is acting more like a conventional 13x12 based on those WOT RPM's vs. speed numbers. Its not surprising it came out of the hole the best. Numbers look consistent on the 13x14 and 13x13.

Assuming these are all older hand finished props with some run time on them, I wouldnt spend a dime "tuning" them. Id be skeptical that a repitched prop could ever provide optimal performance. Personally, Id keep the 3-blade 13x13 around as a back up and sell the other 2 for as much as you can ($50-100/ea) and put the money towards a 541. After you try one, you'll despise the thought of running anything else.

What do you mean 13x13 4-blade is acting more like a conventional 13x12, yes these are oj force, legend props, the 13x14 is fresh with 1 trip out.

TRBenj
09-26-2012, 10:09 AM
13x13 4 blade 4800rpm@44.5mph #1 for torque #3 for mph

13x13 3 blade 4500rpm@46mph #2 for torque #1 for mph


46mph @ 4500rpm is about right for a 13x13. Blade count should not matter. A prop with less pitch (like a conventional 13x12) would turn more RPM for a given speed, consistent with the 44.5mph @ 4800rpm youre seeing with that 4-blade. Put that thing on an accurate machine that can measure pitch and I bet it has a good bit less pitch than the 13x13 3-blade. That would explain the higher WOT rpm's and improved holeshot, regardless of the dimensions that are stamped on the hub.

Either that, or its flexing a lot at WOT (and not translating that extra RPM into more speed), in which case, Id call the prop junk.

ctjahn
09-28-2012, 01:45 PM
My experience from Prestolite Repair. (To date)


I called Prestolite and opened up a ticket a month or so ago (Guestimate) to better understand the return process and where to send it. SHIP DATE: Monday, September 17, 2012, DELIVERY DATE:
Wed 19 Sep 2012 10:51 AM, Phone call 9/25/12 @ 8:13 AM. (about status and how they are proceeding.)


IN SHORT: They are going to send me a reman Malory unit (they said they dont have the materials or parts to reman mine), AND send back my Pertonix and associated stuff from the electronic conversion ALL for $75.00 plus shipping (including reman unit).


I did ask if I could use the same cap, which is still on the motor with the wires (they said yes but I am suspect.)


Will report back when I get it.

Cj


So the new Mallory Distributor arrived (9/28). And have some questions...

I ASSume that I can use the old flame thrower coil? (Pertronix)? (no resisitor)

I ASSume the wiring is the same... but I dont have it (and cant find it for plug wires using the search function...Attachments not opening on posts from 2009. Looking for a drawing I had in the past showed top down. Can someone help point me in the direction? I spent about 30 minutes searching using Wiring, Distributor, Coil, and combinations of words along with looking at FAQ's

I recall for a 351W, #1 is front right; 8 is left rear?

I hoped to just bolt my new cap on to the new distributor when it arrived (which I already had wired from before removing the old distrib but it wont fit on the new distributor = PRestolite versus Mallory

Can someone help me out? At the very least point me to the drawing?

Thx!
Cj

j.mccreight@hotmail.com
09-28-2012, 02:01 PM
Resistor is required for mallory EI it's there for protection of the module, unless your coil already does this. 3 wires on mallory unit, red goes to switched 12v, brown is ground, green goes to neg coil.

ctjahn
09-28-2012, 02:07 PM
Resistor is required for mallory EI it's there for protection of the module, unless your coil already does this. 3 wires on mallory unit, red goes to switched 12v, brown is ground, green goes to neg coil.

Your the man! Thanks.

The top one was exactly the diagram I was looking for! I guess I will have to go check skidim for a resistor. (I think I chucked it in the past)... I think you dont need it with the flamethrower II coil but I would rather play it safe.

Cj

j.mccreight@hotmail.com
09-28-2012, 02:12 PM
Fedex brought me a special package this morning, Acme 541 13x12 CNC 3blade, unfortunatly I work this weekend and it's going to rain all weekend, so I have to wait until next weekend to try it out.

ctjahn
09-29-2012, 08:12 AM
Resistor is required for mallory EI it's there for protection of the module, unless your coil already does this. 3 wires on mallory unit, red goes to switched 12v, brown is ground, green goes to neg coil.


6 and 1 appear to be over the clips. So if I wire it as shown using those as the starting point to ensure proper wiring orientation I should be ok? Or no? (remember going from prestolite to Mallory.

j.mccreight@hotmail.com
09-29-2012, 09:00 AM
both prestolite and mallory should have the same wiring orientation as this is not distributor specific.

TRBenj
10-01-2012, 10:17 AM
6 and 1 appear to be over the clips. So if I wire it as shown using those as the starting point to ensure proper wiring orientation I should be ok? Or no? (remember going from prestolite to Mallory.
The posts can be located anywhere- it will depend on the way the rotor was facing when the distributor was installed. Find the location of the #1 post (where the rotor points when cyl #1 is at TDC of the compression stroke) and follow the firing order around (counter clockwise).

j.mccreight@hotmail.com
10-06-2012, 08:01 PM
Tried out the new acme 541, overall better, almost as much torque as the OJ 13x13 4blade 4750 rpm @ 46 mph. Picked up 250 rpm but mph was the same over the 13x13 3blade. Acme growled abit during turns and on deceleration and didn't hold speed as well in turns as the OJ, but straight line was quiet and smooth and had less rooster tail than the 13x13 3blade. Do I call it good or try another propeller?

Cloaked
10-06-2012, 08:20 PM
...........straight line was quiet and smooth and had less rooster tail than the 13x13 3blade. Do I call it good or try another propeller?That is precisely why I called it good and use the Acme 541 for my boats. The smoothness in particular feels good on my feet (through the absence of vibrations in the floor).

I have used the A-541 for a lot of years on various boats and keep going back to it.

.

ctjahn
10-29-2012, 01:51 PM
So, I didnt "clock" or mark the timing and/or distributor when I took it out. Can I go by the timing marks and try to get it close to TDC and install the new distributor?

Cj

j.mccreight@hotmail.com
10-29-2012, 02:08 PM
yes, sorta,
1)remove #1 spark plug and make sure it's on compression stroke on tdc then line up harmonic timing marks
2)install distributor with rotor installed and line up rotor at where ever #1 cyl cap post is(theoretically it can point at any post and you will just have to rotate the wires around) I would try to use that picture as a reference.
3)set ignition timing while engine running

http://www.youtube.com/watch?v=FHX1yXVyIMg&feature=relmfu