Hard Starting and hotter spark plugs

[nsbluenose]

I have a 1725 with Weber 32/36 DVG. I eliminated the PCV years ago. Starts easily and runs smooth through all gears.

 

[hartmandm]

Tracy,

For future reference, what PCV valve were you using and which manifold?

Thanks,
Mike

 

[Eleven]

Tracy,

For future reference, what PCV valve were you using and which manifold?

Thanks,
Mike

I have a Sunbeam Specialties manifold. Does not have a heater jacket and the PCV inlet is in a plenum directly below the carb. I will have to get the NAPA part number, not sure what it comes off of. The parts guy was trying to match the original one as best he could. Will let you know.

 

[Eleven]

Tracy,

For future reference, what PCV valve were you using and which manifold?

Thanks,
Mike

Mike,
Here is a photo of the box and part. I took it out to see how the car runs without a PCV. It does fine but that hasn't solved all the issues which I am beginning to suspect are not going away. Starts a bit better but still a struggle sometimes, idles crappy. Going to check the carb jets and after that call it a bad job and live with it.

 

[hartmandm]

Napa lists these vehicles for the PCV:

The Forester was a 2.5L 4 cylinder. Impreza had 1.8L to 2.2L 4 cylinders. So probably a decent PCV choice for the Alpine 1.7L engine. Is the hose connection a different size than the stock PCV (1/2")? The Napa site lists the hose connector size as 3/8", but the photo makes it look like it might be larger than 1/2".

I'm not familiar with the Sunbeam Specialties manifold. Does it look like the PCV connection point gets evenly distributed across all cylinder intakes?

Mike

 

[Tim R]

Tracy, assuming that the rough idle is not down to a higher lift camshaft or air leak and that your jets are clean and correct........

... there is a tiny brass screw (on at least some of the twin choke webers) that is not easily visible and sits on an underneath part of the casting. You only see it when looking up from underneath. When I bought a new DGV for a car it just would not idle no matter what I did. I spoke to the technical department and with their help I found this tiny screw and turned it about ⅛ turn and suddenly the car idled like a dream. I am sorry but I am not with the car at the moment and I can't remember exactly where the screw is but it is worth looking for and doing a bit of research on. It ONLY affects tick over idle so it won't change the tune or anything else.

Tim R

 

[Tim R]

Further to my above post this is the screw, it is called the secondary idle screw. https://www.carburetion.com/Products/ProductDetails.aspx?part=64595.005

Find this part, it is 54 in the diagram and you may solve your problem.

Tim R

 

[Eleven]

Napa lists these vehicles for the PCV:
View attachment 21821
The Forester was a 2.5L 4 cylinder. Impreza had 1.8L to 2.2L 4 cylinders. So probably a decent PCV choice for the Alpine 1.7L engine. Is the hose connection a different size than the stock PCV (1/2")? The Napa site lists the hose connector size as 3/8", but the photo makes it look like it might be larger than 1/2".

I'm not familiar with the Sunbeam Specialties manifold. Does it look like the PCV connection point gets evenly distributed across all cylinder intakes?

Mike

Yes, the hose size is one larger. I forced it on because the oil filler out let is smaller. I have since removed the PCV valve. The SS manifold has the PCV located in a plenum directly below the carb so I think yes, the location is good

 

[Eleven]

Further to my above post this is the screw, it is called the secondary idle screw. https://www.carburetion.com/Products/ProductDetails.aspx?part=64595.005

Find this part, it is 54 in the diagram and you may solve your problem.

Tim RView attachment 21822

Son of gun. I changed the Main and Secondary jets this AM to your setting and it is better. I will see if I can find that screw and get to it. Thanks for the heads up!

 

[hartmandm]

Yes, the hose size is one larger. I forced it on because the oil filler out let is smaller. I have since removed the PCV valve. The SS manifold has the PCV located in a plenum directly below the carb so I think yes, the location is good

Did you connect the flame trap / oil filler to the PCV? Normally the PCV is connected to the tappet side cover vent. The flame trap normally is connected to the air filters to have a supply of filtered air. I am curious what setup you had / currently have.

Mike

 

[Tim R]

Mike, the PCV on my Series V did not attach to the tappet chest, it was on the pipe to the rocker cover.

Tim R

 

[Eleven]

Did you connect the flame trap / oil filler to the PCV? Normally the PCV is connected to the tappet side cover vent. The flame trap normally is connected to the air filters to have a supply of filtered air. I am curious what setup you had / currently have.

Mike

The PCV valve was connected to the tappet cover plate on the engine via hose to the plenum directly below the carb. The flame trap is connected to the valve cover at the oil filler neck and runs to the under side of the Weber air cleaner. I this seems to match the WSM diagrams. I suspect you could route it the other way and still accomplish what is needed. At any rate, it is running better without. Will do this for a while and if it seems to work,then I will set up an oil catch tank for the side and valve cover hoses. Hope that makes sense.

 

[Tim R]

Apologies my above post was incorrect, I just checked some photographs. The PCV valve on the Series V was connected to the tappet chest cover plate as you say. Th car runs much better without it. We had a catch tank for a while but it never actually caught anything! As a result we vent both tappet cover and rocker cover to atmosphere now and it all runs beautifully.

Tim R

 

[hartmandm]

Tracy,

Your comment about the oil filler outlet being smaller than the PCV made me wonder if you had a hose connecting the oil filler to the PCV. Sounds like you had the right plumbing setup with the PCV and the Weber. Hope you sort your idle quality issue, maybe by adjusting the secondary idle screw.

Mike

 

[Eleven]

Well, here is the work I have done since I starting this:
Removed the PVC system
Re-jetted the carb (nsbluenose)sent me his specs and mine were different so reset mine)
Re-adjusted the valves (were noisy)
Car is running better than it ever has. Still a little shaky but no where near what it was. I could not find that adjusting screw that Tim R mentioned but decided to leave well enough alone at this point given that it is running well (against my nature!). Unfortunately, it is raining here in Seattle and looks like it will for a while so can't test drive it. European steel and water don't mix, especially with the salt air where I live. These cars rot like pears (I heard that somewhere once) so not tempting fate.
Anyway, I doubt I would have made any progress without the help, encouragement and advice of all of you. Many thanks and have a Merry Christmas and a safe holiday season!!!

 

[pruyter]

Tracy if you use a mirror and hold it under the toppart of the carburettor you will see the screw which Tim mentioned in his post.
I have this Weber conversion installed on my Rapier series IV and with a mirror I could see the screw.

Regards,

Peter

 

[Bill Blue]

I don't understand how the secondary idle screw can be of significance at idle. Doesn't it come into play as the secondary opens? Maybe that is why I was never able to tune my Weber to my satisfaction.

Bill

 

[Eleven]

I could not find that screw on mine so they may not be all the same. Did a short test drive and in the 15 years I have owned this car it is the first time that it felt right!

 

[nsbluenose]

I found that secondary idle screw, didn't know I had one. Haven't touched it - yet. It is located on the drivers side, just inside of the stud holding the card to manifold. Quite small, points up so you need to get a small slot screwdriver from underneath the screw. It adjusts against a lever extending from the throttle. Once you see it, it is so obvious.

 

[RootesRooter]

Is that for all manifolds, including the standard Series IV, or just the recent manifold out of the UK?

In the UK many (probably most) of us that run single Weber carbs do away with the PCV completely.

Tim R