Author Topic: PHF 36 body differences  (Read 2157 times)

omega1

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PHF 36 body differences
« on: October 04, 2016, 06:03:07 AM »
I have been trying to figure out why the right cylinder on my le mans runs consistently richer than the left. Swopping jets left to right makes no difference. Timing,valves all set correctly. Bike runs really well. Then I noticed that the carb body itself is different. Left carb has three passages through the intake manifold while right carb has two! Weird!

Can anyone give me some insight into this?

TIA












Offline Aaron D.

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Re: PHF 36 body differences
« Reply #1 on: October 04, 2016, 06:17:02 AM »
Can we get a wider shot? They don't look like the same carb...

Online John A

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Re: PHF 36 body differences
« Reply #2 on: October 04, 2016, 08:13:23 AM »
There is a difference between the running on the left and right cylinders. One example is from Sonny Angles single carb manifold. I have not seen the intake on a Quota or the newer small blocks with a single carb but my point is that the two different carbs may not be wrong.
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Online Cal3

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Re: PHF 36 body differences
« Reply #3 on: October 04, 2016, 09:07:46 AM »
I have been trying to figure out why the right cylinder on my le mans runs consistently richer than the left. Swopping jets left to right makes no difference. Timing,valves all set correctly. Bike runs really well. Then I noticed that the carb body itself is different. Left carb has three passages through the intake manifold while right carb has two! Weird!

Can anyone give me some insight into this?

TIA

That's interesting, I am re-commissioning an 83LM that has sat for a long time.....it seems to run cooler and richer on the right side. I will try to take a look at my carbs when I get the airbox off of it.











Offline guzzista

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Re: PHF 36 body differences
« Reply #4 on: October 04, 2016, 12:06:02 PM »
Bottom pic/ 3 holes = early type, ( either PHF A or simply S = sinistro ( left) or D= Destro/ Right), should have little bucket/ thimble bowl nut  Second from top pic = later model , 2 holes , large shallow 21 mm Bowl nut. Top  and 3rd from top pic =?  not Kosher, modified, or just a different animal. 
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omega1

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Re: PHF 36 body differences
« Reply #5 on: October 04, 2016, 01:39:45 PM »
Bottom pic/ 3 holes = early type, ( either PHF A or simply S = sinistro ( left) or D= Destro/ Right), should have little bucket/ thimble bowl nut  Second from top pic = later model , 2 holes , large shallow 21 mm Bowl nut. Top  and 3rd from top pic =?  not Kosher, modified, or just a different animal.

The three hole left carb is marked PHF 36BS and the two hole carb is marked PHF 36BD. Both have the bucket/thimble bowl nut which look new so clearly not original part. Both carbs are fitted with identical jetting from the LM2 era, 60 idle, K5 needle, 135 main, 60/3 slide, 38 AP jet.

It just puzzles me what the third hole's purpose and effect is and is this the reason for the right carb to run consistently richer than the left?

Offline Curtis Harper

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Re: PHF 36 body differences
« Reply #6 on: October 04, 2016, 02:25:46 PM »
PHF carbs were used on several models and numerous brands. I would guess right carb is from a different brand IE Ducati Laverda etc.... From a quick glance that is what I would look at. It may also be a 2 stroke carb.
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