Solex rebuild using wheel cylinder hone

[tomolmsted]

Has anyone used a brake wheel cylinder hone to clean up the throttle bores on a Solex 40 PII then install an oversize throttle plate (41mm in my case)? I have no problem paying the professionals to do it, but after spending $35,000 so far on restoration and paying kids's college at a private university, I am getting unpleasant noises from the wife on the money being spent.

Time is not an issue since I am semi-retired.

Tom
69 912

[bobrestore]

I have never tried to do it myself. I believe it is very complicated to get the tolerances correct. You should contact 356 carburetor rescue. they have various services to offer for your Solex carb. they might sell you bodies that have already been cleaned up, bored and new plate installed, if that's all you want.

[Jaems]

If a rebuilt kit won't do it. Then, it is time to let the professional take over. They have everything that is necessary to do a complete rebuilt of the Solex carbs. The Carburetors on the 912 engine can be very sensitive. If you do not get the air, jets, and etc absolutely right for your particular engine.

[bobrestore]

something different but related..... the distributer can get gummed up and the advance hangs up so that the engine idles very high.... if this is one of your problems... high idle... you need to have the distributer rebuilt.. new springs etc...
it happens that the carbs will be all rebuilt and set up only to have the idle not behave because of a gunky distributer....

[tomolmsted]

Groove caused by throttle plate.

Tom,

You "have no problem paying the professionals", but you get "unpleasant noises from the wife on the money being spent" and "time is no issue".

Perhaps investing some time in the relationship with your wife might solve the unpleasant noises and enable you to let the professionals to do the carb job. Remember your 912, sometimes a noise is not caused by a source you expect it to come from ...

Not to offend you, but I couldn't resist.

Otto

[tomolmsted]

Otto,

I post here to get technical responses, not marriage counseling.

These "professionals" do great work and perform a service to the 356 and 912 community. However, I am a STRONG believer in DIY. My Porsche restoration has been a great learning experience and I am still learning. For me it's not the end result but the process getting there. That's how I get the most satisfaction.

If anyone is interested, I will be installing the split shaft to single shaft conversion using the kit supplied by seller ALFA1750 on eBay.

[bobrestore]

what is in the kit?

Tom,

So your relationship and the money you spend is technical. Sorry, but if you expose your private situation in the way you do, you may expect a reaction like mine.

Regarding your response you seem to have serious problems...

Subject closed.

Otto

[Jaems]

On a 912 engine, the first thing you do before anything else, is to adjust the valves, then check or replace the points and set the point gap, the dwell angle, then set the timing. Before even messing with the carburetors. We will assume that you have already did this.

Because you are restoring a classic car. Their parts can and are very expensive and hard to find, especially if it is a Porsche. The venturi on these carburetors is a 32. If you have to change them. Because you have honed out the area. It will be hard to get the right adjustment for a smooth engine. Fore you may have to change the mains, emulsion tubes, and etc. Before you get them sorted out.

So go ahead and work on the carburetors. If you screw them up. You can always find another set of Solexes somewhere for sale and sort them out. Like you said, it is a learning experience. There is also Webers 40 IDF that are real good on the 912 engine. However, you will spend a lot of time sorting them out . They come set up for a VW bug engine, with 28 venturii instead of the 32. There is also 40m Del.

Being single I don't have to worry about these things. As long as my DSH get their two meals a day, some treats, and get to go for rides. They don't care either.

I agree Jaems, and would go for the Solex if originalty counts and for the Weber carbs when affordability, reliability and maintenance are important. Dellorto is a good quality carb, but as far as I've heard, performs lesser than the previous mentioned ones.

Whatever the choice is, you need to be able to make a lot of different jetting combinations to get that smooth running engine. And realize that you need four sets of each combination. In addition you will need a lot of time and patience. Don't forget that environmental influences, like altitude, humidity and temperature have their influence on the right jetting. Even the air cleaner has its influence - so always tune with a new filter.

Otto

[Neil '67 911S]

Hi Tom,

No one answered your original question about using a brake hone. Are you thinking of the springy 3-legged KD tool variety? In my opinion, you shouldn't because there's no guarantee that the hone would make for an acceptably round hole. In fact, you might make things worse.

The throat needs to be properly bored. Carburetor Rescue will do just this task for you (plus fit a matching throttle plate) for $675 versus a pricey $1600 full bore shiny restoration. Check out their site.

SPriceList

[tomolmsted]

Neil,

Yes, I was thinking about the three sprung stones like the KD unit. Your logic makes sense, but I wish I had some junk throttle bodies to try it out. Hone, measure, etc.

[Sweet68912]

I had Webers on the car when I got it a year ago...engine ran fine...then started the restoration process of "all original" & quite the expense but oh well...what would one expect. Bought a set of Solex split shafts on Ebay as that's what my '68 came with. ...they look good but who knows until I fire it up. Hoping they will work well but realistic & have already made contact with Carburetor Rescue (come highly recommended) that I might have to throw back on the Webers when car done soon to drive around while Solex's are being refurbished. Just spoke with Carlo of Dream Car Garage here in my area. He's restoring a '68 912 CA car for client & sent his out somewhere..$2500 later he got them back & like new..I'm like Tom & a DIY guy but leaning toward Carburetor Rescue...:-) Done tons of Holley's, AFB's, Edelbrocks & Rodchesters but will leave these Solex's to the pro's..