Linkert 3 to 4 bolt manifold conversion.

Linkert Manifold

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tomo256
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Linkert 3 to 4 bolt manifold conversion.

#1

Post by tomo256 » Wed May 01, 2019 7:53 pm

Hi.
Can anyone please tell me if a conversion plate is available to convert a 3 bolt linkert manifold to a 4 bolt linkert manifold. I am in touch with the guys at Linkercarbs.com who are hopefully going to build a linkert for my model U stroker. I Dont want to change the manifold as it has had a fair bit of work done to it. I have looked at other threads on carbs and decided on a linkert.
At present it has an S.U. fitted but it just sticks out too far and is damn ugly and will make foot clutch operation a nightmare. Just trying to cover all the bases with regard to fitting it (not sure if it is going to be a 3 or 4 bolt carb, still in negotiation.) If they are not available I guess I can construct one. Has anyone made one before ?
Thanks
Martin



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Re: Linkert 3 to 4 bolt manifold conversion.

#2

Post by Buddhahoodvatoloco » Wed May 01, 2019 8:47 pm

Hombre can be done,
do some serious homework,
throat ID, OD as a example, bolt location, on and on.
But it can be done.

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Re: Linkert 3 to 4 bolt manifold conversion.

#3

Post by tomo256 » Wed May 01, 2019 8:55 pm

Hi.
Yes was pretty sure it can be done, was just hoping someone had done it before me and could shed some light on it.

Martin

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Re: Linkert 3 to 4 bolt manifold conversion.

#4

Post by RUBONE » Wed May 01, 2019 10:06 pm

Several ways to do it, but all will create a longer overall length. It also will need a taper matched bore to function well. Most are a block of aluminum about 5/8-/3/4 thick to allow recessed head screws to attach on one side.

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Re: Linkert 3 to 4 bolt manifold conversion.

#5

Post by tomo256 » Wed May 01, 2019 10:30 pm

Hi Rubone.
Thanks for the reply. I was hoping to go with 1/2” aluminium, half inch is not a lot of extra length overall. Do you know if the bottom 2 bolts are in the same position on both manifolds or not. That would really help the cause.

Martin

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Re: Linkert 3 to 4 bolt manifold conversion.

#6

Post by RCamp » Wed May 01, 2019 11:11 pm

Martin,
I run a M53 on my UL. I just cut the flange off my UL manifold and used a bad Pan manifold with a good flange as a donor.
Cut the flange off it and brazed it to my UL. Been working well for thousands of miles.

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Re: Linkert 3 to 4 bolt manifold conversion.

#7

Post by Buddhahoodvatoloco » Wed May 01, 2019 11:39 pm

Tomo, Tomo, here's a empirical solution. :lol: There's other ways, but here's a simple efficient way. Unless your going to machine one, then have at it, and share pics of your journey :wink: .
RCamp wrote:
Wed May 01, 2019 11:11 pm
Martin,
I run a M53 on my UL. I just cut the flange off my UL manifold and used a bad Pan manifold with a good flange as a donor.
Cut the flange off it and brazed it to my UL. Been working well for thousands of miles.

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Re: Linkert 3 to 4 bolt manifold conversion.

#8

Post by RUBONE » Thu May 02, 2019 1:47 am

The M53 is a nice option since it was originally a flathead carb and minimal changes are needed to function well. And bottom holes are not in the same place. The width is the same but the centerline of the bore is off. Here is a picture of a three bolt gasket on top of a 4 bolt. R Camp's solution works well, but you cannot save the original manifold.
DCP_4391.JPG
DCP_4391.JPG (44.67 KiB) Viewed 414 times
I have used DC Linkerts in the past as they are very short. The adapter would be two bolt for them.

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Re: Linkert 3 to 4 bolt manifold conversion.

#9

Post by tomo256 » Thu May 02, 2019 7:20 am

Guys.
Thanks for the replies, much appreciated, RCamp, brilliant solution and so simple and doesn’t affect the porting and relieving of the existing manifold. Exactly why I asked the question. Certainly beats the hell out of trying to countersink hidden bolts etc. Chances are I will have to make a flange as people tend to hang onto stuff over here even damaged stuff. Still little bit of filing is therapeutic I find and rewarding if it turns out ok. Rubone thanks for the heads up on the bolt pattern. I will document the progress and post pics. Can anyone recommend a specialist carb builder with experience of strokers if my original choice doesn’t come through.
Martin

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Re: Linkert 3 to 4 bolt manifold conversion.

#10

Post by Buddhahoodvatoloco » Thu May 02, 2019 3:10 pm

Linkerts only I think.
http://www.linkertcarbs.com/linkert.html
good guys, or as we say en el barrio, good woods.

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Re: Linkert 3 to 4 bolt manifold conversion.

#11

Post by tomo256 » Sat May 04, 2019 7:52 pm

Update guys.
I have ordered an M74 Linkert from www.linkertcarbs.com who are going to set it up for my stroker. Now I have to construct a manifokd to take a 4 bolt linkert. A bit of a long shot but does anybody have a 4 bolt linkert manifold that they are willing to do a deal on, preferably in the U.K. or Europe.
Martin.

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Re: Linkert 3 to 4 bolt manifold conversion.

#12

Post by RooDog » Sat May 04, 2019 10:11 pm

Just a question:
How about just cutting a 4-bolt flange, using a gasket for the pattern, out of 3/16 steel plate and then just welding, or brazing it to the Y manifold after cutting off the original 3-bolt flange. Or even a 2-bolt flange for a DC carbby? Is there some technical reason why this wouldn't work?
...RooDog....

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Re: Linkert 3 to 4 bolt manifold conversion.

#13

Post by tomo256 » Sat May 04, 2019 10:21 pm

RooDog.
No reason whatsoever, just trying to make life easier for myself. In all fairness I have resigned myself to making one, just hoping there is a spare one kicking about in Europe.
Martin

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Re: Linkert 3 to 4 bolt manifold conversion.

#14

Post by tomo256 » Tue May 14, 2019 9:25 pm

Well guys thanks for the helpful advise, I finally got around to converting my 3 bolt manifold to 4 bolt. I said I would report back with some photos,
2.JPG
First photo is as a 3 bolt manifold that has been converted to use rubber band connectors to the manifold.
2.JPG (17.7 KiB) Viewed 250 times
3.JPG
With new 4 bolt flange machined.
3.JPG (17.48 KiB) Viewed 250 times
4.JPG
With 4 bolt manifold flange machined.
4.JPG (15.03 KiB) Viewed 250 times
5.JPG
Wired together for brazing.
5.JPG (14.8 KiB) Viewed 250 times
7.JPG
Brazed.
7.JPG (14.08 KiB) Viewed 250 times
Once again thanks for the advise.

Martin

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