Search found 1198 matches

by franz
Fri Apr 10, 2015 11:43 am
Forum: Propane Forum
Topic: What's this plunger for? (OHG X450)
Replies: 16
Views: 3126

Re: What's this plunger for? (OHG X450)

For pipe threads, I prefer Teflon paste. Rectorseal is a widely recognized threadseal. It seams that every time I had a threaded joint leak, it was with tape. I use it for water joints but no longer for threaded gas joints, and that includes high pressure CNG if that makes any difference.

Franz
by franz
Thu Apr 09, 2015 4:23 pm
Forum: Propane Forum
Topic: What's this plunger for? (OHG X450)
Replies: 16
Views: 3126

Re: What's this plunger for? (OHG X450)

You may leave it intact, I am in the process of filing a formal Violation of Copyright against the site in question. Everyone who has obtained this book via legal means is clear, that includes anyone who received my book by me personally or through one European contact who has my permission to distr...
by franz
Thu Apr 09, 2015 9:31 am
Forum: Propane Forum
Topic: What's this plunger for? (OHG X450)
Replies: 16
Views: 3126

Re: What's this plunger for? (OHG X450)

That site doesnt have my permission to show that book and is indeed in violation of my copyright. I will be contacting them. For what its worth, I dont know that publisher nor did I give them permission to show my book. I may put the book up for sale on my site, thanks for suggesting Frank. I've bee...
by franz
Sat Apr 04, 2015 9:47 am
Forum: Propane Forum
Topic: What's this plunger for? (OHG X450)
Replies: 16
Views: 3126

Re: What's this plunger for? (OHG X450)

Thanks for the plug, Storm. The piston serves two purposes, the one you mentioned, where it allows extra fuel, plus it closes the vent to the top cover, allowing the air valve to raise, decreasing air restriction. By the air valve lifting, the metering pins also raise, allowing additional fuel, some...
by franz
Sat Mar 28, 2015 5:39 pm
Forum: Propane Forum
Topic: Propane Vapor Barrier
Replies: 7
Views: 1683

Re: Propane Vapor Barrier

The problem is that the relatively low ice temperature increases the relative density of propane where it starts to assume some of the properties of a liquid. Not yet a liquid but it begins to be "lazy" and wants to settle before ignition. Those in colder climates might relate to this better than I,...
by franz
Sat Mar 21, 2015 11:08 am
Forum: Propane Forum
Topic: Heavy towing
Replies: 23
Views: 3865

Re: Heavy towing

You hit it on the head when you said the cooling system must be kept top notch. The model E can provide continuous fuel for about 325 bhp when at full operating temp at 100 deg C. Many people want to put in 160 deg thermostats and that causes problems with the vaporizer along with oil gumming. The m...
by franz
Thu Jan 15, 2015 10:21 am
Forum: Propane Forum
Topic: 454 valve seats
Replies: 21
Views: 6753

Re: 454 valve seats

In a civilized manner, I respectfully add that any reference to ideal air-fuel ratios and the perfect ignition timing are moot points. Combustion chamber and piston crown shapes, bore to stroke relationships, cam timing and overlap, valve position, and compression ratios all play a factor. For many ...
by franz
Wed Jan 07, 2015 3:37 pm
Forum: Propane Forum
Topic: 425 w/ 'just' four throttle plate screws...
Replies: 9
Views: 1814

Re: 425 w/ 'just' four throttle plate screws...

On more than one conversion I had the throttle blades rub against a mis-aligned gasket causing the problem you describe. A binding throttleshaft would be due to a warped baseplate or mixer body, neither of which I have seen before. Also, be sure you block the center screw opening on the throttle pla...
by franz
Wed Jan 07, 2015 3:32 pm
Forum: Propane Forum
Topic: IMPCO endorsed mod ? air bleed hole sizes
Replies: 5
Views: 1307

Re: IMPCO endorsed mod ? air bleed hole sizes

Like C3H8 stated, the holes are there to transfer vacuum, with the blockage providing the results he stated. The hand written number indicates a flow bench rating as compared to a reference unit. Generally speaking, numbers below "90" are lean biased while numbers above that are rich biased. I have ...
by franz
Wed Sep 17, 2014 8:59 am
Forum: Propane Forum
Topic: Decision Time: X-450a or Impco 425
Replies: 6
Views: 2260

Re: Decision Time: X-450a or Impco 425

I've been very busy working on my consulting business that I missed the last couple of posts. I do not know of Mr. Mullen and look forward to reading his input as well. My experience with ANY of the air-valve mixers when placed above a standard carburetor is that it alters the metering, enough that ...
by franz
Mon Sep 08, 2014 8:44 am
Forum: Propane Forum
Topic: Decision Time: X-450a or Impco 425
Replies: 6
Views: 2260

Re: Decision Time: X-450a or Impco 425

The X-450 can be modified for vacuum lift for dual fuel use. You will need to remove the top cover and drill the very top for a vacuum fitting, then to a solenoid connected to a switch when on gasoline. Be sure the vacuum fitting is in the very top and not the side. Clearance may be an issue. Be adv...
by franz
Sun Aug 31, 2014 9:18 am
Forum: Propane Forum
Topic: 1988 F350 with smog control issue
Replies: 10
Views: 2061

Re: 1988 F350 with smog control issue

Even though conventional fuel systems were closed loop in the 80's, closed loop wasnt required on alt fuel vehicles until around 1992, based on the assumption that the alt fuel was cleaner. There were several companies making closed loop controllers for these early applications and many of us adapte...
by franz
Sat Aug 30, 2014 6:47 pm
Forum: Propane Forum
Topic: 1988 F350 with smog control issue
Replies: 10
Views: 2061

Re: 1988 F350 with smog control issue

High NOx is created by running excessively lean. The HC isnt too bad for an open loop engine (no computer controls it looks like). There are four gas valves for the Impco 424, the one most likely for yours is the #16, the standard open loop valve. The #44 is pretty lean at cruise and the #51 is rich...
by franz
Sat Aug 30, 2014 4:56 pm
Forum: Propane Forum
Topic: IMPCO part # AB1-26
Replies: 10
Views: 1855

Re: IMPCO part # AB1-26

There used to be. The only number that remained consistent was their silver label on the body or cover. The manufacturing date was very helpful. Take "190912". Take the first two numbers and reverse them. That gives the year, in this case, 1991. The 09 was the month, followed by the day. Sept 12, 19...
by franz
Thu Aug 28, 2014 9:56 am
Forum: Propane Forum
Topic: IMPCO part # AB1-26
Replies: 10
Views: 1855

Re: IMPCO part # AB1-26

The AB1-24 is a throttlebody assembly, while the AB1-28 is a mechanical primer used in a Cobra. None of the catalogs I have list the AB1-26. The AD1-26 is a secondary diaphragm and still available. I didnt see any reference to a compensator in my series of catalogs and really dont remember the numbe...