Johnson V4 How can i add choke primer to choke solenoid carbs ????

spybot

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Hi all in my quest for a transformed engine i need help on one point just now.
I am going to add these carbs (Fitted with choke plates) I will remove these (I think????)
I want to run these with a primer solenoid which is already on my engine ( Johnson V4 85hp)
I know it can be done but i cant find any info on how to do it. I read somewhere that you buy a service kit for or gasket for the new type of carbs then there will be a hole in the gasket that you drill out and fit a nipple to which you attach the two small rubber hoses from the primer solenoid. Is it as simple as that???
I know i will be re jetting the carbs and rebuilding them. So at present i don't need info on the carbs, just a pointer in the right direction on what to do.
In a nut shell do i just drill the holes fit the nipples and disregard the choke plates ????
Or do i keep the plates in place ????
Or should i go for the choke solenoid over the primer ????
Any help with a pic of where to drill would be great.
 

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Joe Reeves

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Other than installing the proper carburetors with the proper jetting... OR... the proper intake manifold, either component with the proper primer nipples... I would say that you have some interesting machine work located in your future. I do wish you luck.
 

spybot

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Hi Joe thanks for the reply
I have read a lot of your posts and i have learned a few things from them.
I have both sets of carbs plus both manifolds. I was just thinking if there was a way of combining the two ie swap carbs to the other manifold ???
I intend to document my transformation as it may help others on here
I shall take the humble V4 85hp and turn her into a 140hp mild tuned for fast but reliable loch ( lake) use. The main thing is reliable and only needing general servicing here is hoping anyways
 

interalian

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I converted a pair of '79 flappy choke 140 carbies to primer. Hard part was finding the right drill size. Harvested the nipples from a pair of 90hp carbs.

But yeah, can't make 140 unless you have the right block and exhaust. Many have tried...

IMG_0708_zpsahrt1vjm.jpg


IMG_0704_zpsefa1dtxp.jpg


IMG_0702_zpsxruinx0a.jpg
 

spybot

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Hi Interalian thanks so much for the photos thats i have been looking for. What size of drill did you use ?
Did you remove the choke plates completely ?
Regards the 85 to 140 The stroke and cc are the same you are correct the 140 has the bubble butt exhaust and a slightly different block but I will have the block machined to take the exhaust. I have the carbs, the H/C heads from a 140, and the exhaust. I will do some mild tuning and start a thread so everyone can see my progress/fails along the way lol
Chers
 

racerone

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What size are intake ports on the 85 hp block compared to a 140 hp ??
 

Faztbullet

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The intake and exhaust porting is different...a 85 the exhaust ports are about the size of a nickel and a 140 the size of a quarter. Also you need the filler blocks to go with the exhaust and then have the block milled to match them or exhaust wont seal.Like stated you cannot turn it into a 140 by just bolting on parts.
 

Chinewalker

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And it's not just a matter of making the ports bigger. There's some voodoo involved, too, so that port timing is where it needs to be. FAR easier to start with a 115 or 140 block and go from there. Later GT100 blocks also use the big ports.
 

interalian

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Hi Interalian thanks so much for the photos thats i have been looking for. What size of drill did you use ?
Did you remove the choke plates completely ?
Regards the 85 to 140 The stroke and cc are the same you are correct the 140 has the bubble butt exhaust and a slightly different block but I will have the block machined to take the exhaust. I have the carbs, the H/C heads from a 140, and the exhaust. I will do some mild tuning and start a thread so everyone can see my progress/fails along the way lol
Chers

I don't remember what size drill I used - I experimented with a scrap of aluminum plate until I had the right size for a tight 'tap fit'. As the photos show, choke flap plates are gone. Primer system works way better than flappy plates.

As for intake ports, I remember looking at them and it appears OMC just made the holes a lot larger on the 140 compared to the 90 I started with. Not sure how much 'voodoo' was involved - they may well have just used a larger mill on the same center. There's no port extension in the cylinder, just large round holes. If you send me some $$ I'll pull a bypass cover off my Frankenmotor and make some measurements (lol) - I still have the old 90 block for comparison.

Yes, you will need the exhaust filler plates and the bubble butt exhaust, and you'll need to cut the exhaust chest bottom rib like the 140 has. As noted, much easier to start with a 140 block and work with it.

IMG_0756_zpsaqrdjpva.jpg
 

spybot

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As for intake ports, I remember looking at them and it appears OMC just made the holes a lot larger on the 140 compared to the 90 I started with. Not sure how much 'voodoo' was involved - they may well have just used a larger mill on the same center. There's no port extension in the cylinder, just large round holes. If you send me some $$ I'll pull a bypass cover off my Frankenmotor and make some measurements (lol) - I still have the old 90 block for comparison.

Thanks inter I thought this forum was helping each other out and not sending someone some "$$" to check out something on their engine. I am sure and i checked through your engine build thread that NO ONE charged you for advice or for their time.
So much for the ethics of this forum
 

interalian

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Thanks inter I thought this forum was helping each other out and not sending someone some "$$" to check out something on their engine. I am sure and i checked through your engine build thread that NO ONE charged you for advice or for their time.
So much for the ethics of this forum

I guess the subtlety of the (lol) was lost on you, and if you think 'helping you out for free' involves removing a part off a finished and running engine is going to happen, you're mistaken.

I would suggest you find yourself a 140 block, at least to measure for yourself. You'll need it anyway for the exhaust fillers and other parts.

I'm out.
 

V153

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I guess the subtlety of the (lol) was lost on you, and if you think 'helping you out for free' involves removing a part off a finished and running engine is going to happen, you're mistaken.

I would suggest you find yourself a 140 block, at least to measure for yourself. You'll need it anyway for the exhaust fillers and other parts.

I'm out.
In his meager defense Spybot's from Scotland. But then again so am I, by proxy ...
 

V153

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Evidently sarcasm don't travel too well ...
 

interalian

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Well, back in the 9th century when my ancestors sacked Ath Cliath (Dublin), some noses must have gotten out of joint.

Watch out for the Dubghaill.
 

spybot

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Hi V153
Would you care to share you thoughts on your "Nine Paged 140"
Was it quite easy following the pages or were there things that you done differently ?
 

V153

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The intake and exhaust porting is different...a 85 the exhaust ports are about the size of a nickel and a 140 the size of a quarter. Also you need the filler blocks to go with the exhaust and then have the block milled to match them or exhaust wont seal.Like stated you cannot turn it into a 140 by just bolting on parts.
Porting is the same '78 up. Since his is a 1980 it should be same as the higher hp models. EXCEPT he'll need to cut the exhaust bridge. And yes mill the filler blocks/block. But that should be the only serious machine work?

That said, I thought by 1980 they had gone to the primer vs butterfly type III carbs? And somewhere in there they went to a larger main crank bearing/journal.

One more thing. In the US at least I don't think we had a 1980 85hp. Believe it was the 90 by then. Sure about the year Spybot?
 

V153

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And something to consider before milling is running without the exhaust filler blocks. Told it hurts the midrange a lil, but ya wind up with a couple hundred rpm up top? Plan to try this on a '79 115 I got sittin in the craport.
 

V153

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Hi V153
Would you care to share you thoughts on your "Nine Paged 140"
Was it quite easy following the pages or were there things that you done differently ?
Buddy of mine sawed on it. I just take the chit apart and put it back together ...

But here's what I can tell you:

'77 140 block with scalloped cylinders, rod slots cut, scalloped 030 Wiseco teflon coated pistons, squaring of the ports, '78 hi comp heads.

'92 intake w/fuel recirc lines, '83 140 type III carbs with stock jetting (Too rich actually.) Carson reeds with stuffers.

Single powerpack CDI ignition and '92 flywheel.

'77 drilled mid with megaphone tuner.

Fastest prop is a 13 3/4 x 25 OMC SRX. (66.7) Second is a 13 1/2 x 26 Raker. (65.3)
 

spybot

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Hi V153 thanks for the info. My engine is a 1980 model number J85TLCSA.
Can you explain or show what part of the exhaust was drilled out ?
I have a Bubble but from a 140 to go on (i will have the blocked milled ) once i have done the transformation should i look for a diff rent one ?
Like the megaphone tuner ? Any youtube vids on one ?
I read about taking the fillers out seems its a good idea on the V4s
Looking at getting the pistons and block done as per the "9 pages" Will look at lightening the fly wheel as well.
I would really like to know about the exhaust though drill holes
found the site for the megaphoone tuner
 
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