Triple OER/SK carb issues, not balancing (SOLVED)

[240260280]

Process of elimination.

You need to remove carb lid and disassemble choke assembly to inspect thoroughly.  

 

Edited October 25, 2017 by 240260280

[240260280]

Duh.... I am dumb!   The SK's have the cold start plunger up in the lid... so it is easy to take apart!

Part #21 is the plunger.

 

 

 

For quick and dirty check, you may be able to cover this port (below) with tape to block any leak to manifold at idle:

 

Edited October 25, 2017 by 240260280

[Jazz86]

15 hours ago, 240260280 said:

Duh.... I am dumb!   The SK's have the cold start plunger up in the lid... so it is easy to take apart!

Part #21 is the plunger.

 

 

 

For quick and dirty check, you may be able to cover this port (below) with tape to block any leak to manifold at idle:

 

Nope, sadly the plunger works and seals correctly. ?

[gundee]

Personally those carb to manifold gaskets look like junk. If o-ring type. Toss them. They like to pop out if not installed carefully.

I have replaced a couple at the track for guys having issues. Install bakelite style with gaskets on both sides. Then start your tuning all over.

[Jazz86]

Okay, I finally managed to get the carbs balanced at idle by fixing various gaskets and bending back a few old bits of metal. But now there is another issue. The carbs rev just fine and they sound amazing but at part throttle the #2 carb starts to pop again.

1. Balanced at idle

2. Popping out exhaust and carb #2 at part throttle, around 2.5k rpm and holding it.

3. Engine revs up super quickly so no complaints about the accelerator pumps

[240260280]

Lumens nailed it! It is strange how spraying carb cleaner around these areas did not bring the problem to light earlier?

 

btw our I6 engines are not prone to foaming gas as they are very well balanced at all rpms, so shock mounting carbs (fuel bowls) is not needed. However,  road vibrations will shake the heck out of the needle valves and wear them out rather quickly thus the need for shock mounts.

Edited October 26, 2017 by 240260280

[240260280]

Popping/spitting out of any carb is usually a fuel delivery issue (not enough).   Try to find the throat that is spitting then thoroughly check the jet values so they match the others and were not drilled or soldered in the past. Also check the orifices of the jets for blockage and or debris.   Likewise check the passages in the carb for debris, including the progression holes and idle enrichment hole.

[Jazz86]

A big THANK YOU to all who has helped me. The car is now running and driving and on the road again. 

[Patcon]

3 hours ago, Jazz86 said:

A big THANK YOU to all who has helped me. The car is now running and driving and on the road again. 

What was the total solution?

[Jazz86]

7 hours ago, Patcon said:

What was the total solution?

The short list of things done

1. Repair bent shafts and rotating internals of carbs

2. Rejet to allow the progression holes to work better

3. Adjusting the idle mixture and idle speed screws in a very delicate fashion, seeing a cause and effect. All the tuning books provide general and vague information which is not helpful.

4. Lots of spark plug reading and road tuning.

[240260280]

Glad you got them sorted.  Measuring Air/Fuel ratios under different conditions will be the next step in optimizing.

[esmit208]

On 10/26/2017 at 6:20 AM, 240260280 said:

Lumens nailed it! It is strange how spraying carb cleaner around these areas did not bring the problem to light earlier?

 

btw our I6 engines are not prone to foaming gas as they are very well balanced at all rpms, so shock mounting carbs (fuel bowls) is not needed. However,  road vibrations will shake the heck out of the needle valves and wear them out rather quickly thus the need for shock mounts.

SHOCKS MOUNTS........Explain please.