Ford Solenoid Hot Start installation instructions, Mark Henry's method Options

[porschetub]

Because this comes up so often I decided to make a tutorial on how I install the Ford solenoid.

The Ford solenoid fixes the common hot start problem of Bosch starter solenoid and it also reduces the load on the ignition switch. Although these instructions are for the 914 all aircooled VW's and Porsche often suffer from this problem and with minor changes this can be done to any car.

The issue occurs because the Bosch starter solenoid needs a full 9 volts to kick in. The combination of age, heat, corrosion, many connectors, a small ignition switch and wiring running to the dash and back can degrade the volts to less than the 9V required.
The Ford solenoid only needs about 3 volts for the 12V version and even less for the 6V which for our purpose works no problem.

My installation drills no holes in the car, not a single factory wire is cut, no in-line fuses, fully reversible and simple with no added bullshit.

Please this is not a discussion on if you prefer the wimpy (IMO) Bosch horn relay, want to cut and hack in a new wire or believe throat singing Vajrayana chants is a better method, start you're own thread.

Of course as with any electrical trouble shooting the first order of business is always clean all of your grounds and make sure the chassis to transmission ground strap is in place and in good condition.

I'll start right away with the money shot of the completed installation to show how clean this can be done.

Ok I'am in on this,is there a part number for the solenoid ? any idea if I could pick it up on the west coast so I can ship for a reasonable price to my country,thanks Mark.

[Mark Henry]

Standard SS-558 is the 6V single small post, works fine at 12V and takes less amps to kick than the 12V.

Standard SS-588 is the 12V two small post, works fine. Also called SW3

I prefer the "Standard" brand name.

They sell Fords in NZ, you should be able to get it local.
They were on all kinds of cars and trucks, huge number of different manufactures part numbers.
Evilbay ads below have a list of vehicles. First link is 12V, 2nd is 6V:

http://www.ebay.com/itm/Starter-Solenoid-M...4xS&vxp=mtr


http://www.ebay.com/itm/Starter-Solenoid-S...3.c100033.m2042

[porschetub]

Standard SS-558 is the 6V single small post, works fine at 12V and takes less amps to kick than the 12V.

Standard SS-588 is the 12V two small post, works fine. Also called SW3

I prefer the "Standard" brand name.

They sell Fords in NZ, you should be able to get it local.
They were on all kinds of cars and trucks, huge number of different manufactures part numbers.
Evilbay ads below have a list of vehicles. First link is 12V, 2nd is 6V:

http://www.ebay.com/itm/Starter-Solenoid-M...4xS&vxp=mtr


http://www.ebay.com/itm/Starter-Solenoid-S...3.c100033.m2042

Thanks Mark,most of our Fords come from Australia but having said that there is a lot of USA classic cars imported from the west coast so should be over to find one here,cheers (IMG:style_emoticons/default/beerchug.gif)

EDIT...got one on Ebay for less that $10 free shipped,NO way I could get one in my country for that,great write-up Mark .

[Mark Henry]

One fail point I was told, but have no direct proof (anecdotal) was that a cheap Chinese relay had failed. That why I recommend the "Standard" brand of relay's.
I've never had a Standard relay fail other than the one that fell apart from severe corrosion. This was after 8 years of winter service on heavily salted roads.

[porschetub]

Ha Ha funny ,Chinese ones are out there,really moved away cheap but not much cheaper ,rest assured got the Standard part ,thanks again.

[Tbrown4x4]

The tabs are available at O'Reilly's Auto Parts in packs of 10.

BWD part # CT948. Under $6

[11tenths]

Hey Mr. Henry- it worked!

Well, not at first... When I turned the key... nothing. Then I recalled you saying there's a 50/50 chance it would be either terminal (I had a two post version) so I switched the connection and "Viola"; success!



Much thanks- Harry

[914Toy]

One fail point I was told, but have no direct proof (anecdotal) was that a cheap Chinese relay had failed. That why I recommend the "Standard" brand of relay's.
I've never had a Standard relay fail other than the one that fell apart from severe corrosion. This was after 8 years of winter service on heavily salted roads.

Hi Mark,
Surprised to see that no ground wire is needed to be attached to the non used terminal in your application of the Ford relay switch?

[Mark Henry]

One fail point I was told, but have no direct proof (anecdotal) was that a cheap Chinese relay had failed. That why I recommend the "Standard" brand of relay's.
I've never had a Standard relay fail other than the one that fell apart from severe corrosion. This was after 8 years of winter service on heavily salted roads.

Hi Mark,
Surprised to see that no ground wire is needed to be attached to the non used terminal in your application of the Ford relay switch?

Because the metal bracket on the solenoid is bolted to the starter mounting stud, there's your ground for the solenoid. (IMG:style_emoticons/default/wink.gif)

[914Toy]

One fail point I was told, but have no direct proof (anecdotal) was that a cheap Chinese relay had failed. That why I recommend the "Standard" brand of relay's.
I've never had a Standard relay fail other than the one that fell apart from severe corrosion. This was after 8 years of winter service on heavily salted roads.

Hi Mark,
Surprised to see that no ground wire is needed to be attached to the non used terminal in your application of the Ford relay switch?

Because the metal bracket on the solenoid is bolted to the starter mounting stud, there's your ground for the solenoid. (IMG:style_emoticons/default/wink.gif)

(IMG:style_emoticons/default/beerchug.gif)

[gothspeed]

Nice and functional, i have too many stories on not being able to start my old LE back in the day. This solenoid took the worry out. Thank you for the great write up. I have to do this when i get the engine back in (IMG:style_emoticons/default/beerchug.gif)

[Mark Henry]

This drawing is mine from back in the early days of the 914world, then part of the club.

(IMG:http://www.914world.com/bbs2/uploads/post-9964-1514863838_thumb.jpg)

[Mueller]

Mark,

Would you recommend this setup for the Hi Torque mini-starters?

[HalfMoon]

Mark,

Would you recommend this setup for the Hi Torque mini-starters?

I actually did this on my Hi-torque about a year ago. The end of hot start problems and so easy even an old coot like me pulled it off.

[Mueller]

Mark,

Would you recommend this setup for the Hi Torque mini-starters?

I actually did this on my Hi-torque about a year ago. The end of hot start problems and so easy even an old coot like me pulled it off.

Thanks, slowly gathering parts for the engine swap!

[jkb944t]

Very nice write-up and I will add it to my to do list this winter. Thanks for all the effort.

Jeff B

[StratPlayer]

My car has this mod.

[76-914]

Great write up- Admins, please add this to the Classics
One question: how is the Ford solenoid different from using a 50 amp relay. Many hot-start kits and threads in The Garage use the smaller relay. Just curious as to the pros and cons... (IMG:style_emoticons/default/smile.gif)

I don't want an argument as to which is better but this is my logic:

1/ I've been doing this forever, not about to change. Before me guy's like Gene Berg have been doing it since the 60's, so this has been a mod done for over 50 years.

2/ The Ford solenoid is waterproof, at least damn water resistant, the SPST relay is not at all. So you must mount the bosch horn relay in the engine bay, run wires through the grommet, tap into a power source, use a fuse, drill a mounting hole and cut the factory wire or at least make an extension/adaptor.

3/ the SPST relay may be 30-50amp which should be enough on paper, but it still has very small contacts. The Ford solenoid must be rated for at least 500 cranking amps, likely much more.

4/ I've personally only had one failure, one that was so badly corroded after 8 winters that the bracket/bottom rusted right off at the rivets and the solenoid literally spilled it's guts in my hand when I took it off.
I've replaced several perfectly good looking SPST relays with a ford unit.

Technically I guess you can say I've had two failures, as a rookie I bent the mount by reefing on the plastic housing and broke one. That's why I instruct you to only bend the mount using two pliers, experience.

5/ The solenoid is fastened to the transmission starter bolt, not the body, so there's almost no vibration strain on the wires.

6/Unless you run across a concours weenie who likes to crawl under cars, just to be an ass pointing out everything that is not factory on a person's 914, you're the only person that will ever know.

7/ When I turn the key the first thing I like to hear is a spinning starter.

8/ I'll think of more reasons, hold my beer.

9/ KISS, this is such a simple fix.

If any of you guys who can't stand the thought of a Ford part on a Porsche, but have a Rennshifter, well you better toss that puppy in the trash.
Jwest now makes all his parts, but the early versions were a modified Ford Mustang shifter. The basic design has not changed.
So send that puppy to me and I'll dispose of it properly, I hate them so much I'll even pay you the shipping. (IMG:style_emoticons/default/biggrin.gif)

You touched on this #2 but I'd like to add that the Ford relay was designed to operate in the engine compartment which becomes quite hot at times. Also, installed next to the old batteries that emitted some pretty corrosive vapors.

[76-914]

I bet the Cap'n would approve, but Slits would still bitch about something...

I miss them a lot, but your posts go a long way towards filling the gap they left.

Nice job (IMG:style_emoticons/default/beerchug.gif)

Cheers- Harry

Actually you've got that bass ackwards, Slits was a proponent and offered the Ford relays to us for $6; or less if he liked you. IIRC, Cap't Crusty was in the camp of those who oppose it. One thing is for sure; the opposing Camp's numbers have dwindled in the past couple of years. (IMG:style_emoticons/default/beerchug.gif)

[Rand]

I bet the Cap'n would approve, but Slits would still bitch about something...

I miss them a lot, but your posts go a long way towards filling the gap they left.

Nice job (IMG:style_emoticons/default/beerchug.gif)

Cheers- Harry

Actually you've got that bass ackwards, Slits was a proponent and offered the Ford relays to us for $6; or less if he liked you. IIRC, Cap't Crusty was in the camp of those who oppose it. One thing is for sure; the opposing Camp's numbers have dwindled in the past couple of years. (IMG:style_emoticons/default/beerchug.gif)

I confess to having been in the last camp, and now a dwindler. I used to think it was dumb because, after all, the switch is NOT a high current circuit and the real relay is the starter solenoid! The real current happens at the starter solenoid where the big juice comes straight from a big cable to the battery. Some people seem to have the misunderstanding that all the current that cranks the engine runs through the starter switch. Which is pure ignorance.

After all that, I have to say while I don't think it's a necessary upgrade I have learned to respect it. A little less current going through the ignition switch is a good thing.

Mark's thread is a great contribution here.