Distributor cap vent VCV issue

[Landpimp]

no more micro explosions but I still have cab farts. Everything is working like its suppose to......but it must not be

 

[OGBeno]

These are still on order unfortunately with a moving ETA from Toyota. We are now looking at late August.

That means these are being manufactured for the order by the supplier. (IIRC, either Denso or Aisan).

 

[OGBeno]

Finally got these in!! 50 of them!

All orders have now been filled.

 

[OGBeno]

I am going to be doing an October special on these VCV'sso stay tuned.

 

[Output Shaft]

 

[Miloslavich]

Beno,

still doing a special on these? the month is almost out!

 

[NOSAJ]

Can someone please chime in. I got my 90925-03192 today and I was going back over the hose routing. In the diagram post #12 on page 1 shows Y & X to air cleaner, s to intake, and z to the dizzy. However in the pic and also in the write up it states y goes to air cleaner, s goes to intake, and Z & X goes to the dizzy. I am assuming that the diagram is wrong and the write up and the picture is right. Please help!

 

[Output Shaft]

Pipe "S" is on the other side of the new VCV, so the vacuum hose needs to be routed under the air cleaner to reach around to it.

The drawing is from the FSM for the original FJ60 VCV which has pipe "S" on the other side.

 

[NOSAJ]

Got it! Thanks! Had a melted distributor rotor this week and I really hope this fixes it!

 

[cuencanolenny]

Another mud member sent me this link today in response to my new thread regarding what kind of distributor I "found" in a '79 2F I installed in my '70 FJ40. My question was with regards to the two holes in the cap. So this link is talking about ozone venting, which I was unaware of. So I did some checking online and find these valves are $5.00-$15 on Summit. It is a simple one way valve. So why is it so doggoned expensive, and complex, for the Land Cruisers? I also found references to just drilling a hole in the cap to vent. Also saw that on some Corvette engines there are three holes in the base of the distributor for venting.

 

[FJ40Jim]

Link to VCV at Summit?

 

[cuencanolenny]

http://www.summitracing.com/int/sea...sortorder=Ascending&keyword=distributor check

Here Jim, they are listed under "Distributor Check Valve." A similar entry on google will come up with a variety of other options as well. Some I found were as low as $5.00.

 

[FJ40Jim]

That's a check valve, not a vacuum controlled valve.

 

[cuencanolenny]

I'm confused Jim, it has connections for vacuum hoses. And as I understand the other discussions in this thread the purpose is to allow evacuation from inside the distributor cap with engine running and to prevent gas fumes from going back into the distributor when the engine is off, hence, a one way valve.

 

[Output Shaft]

The Toyota vacuum control valve (VCV) uses vacuum on one port to open the valve. Air (or ozone) can then flow freely without any restriction.

A check valve, like the one shown on Summit, is a simple flapper valve. Check valves allow air to flow in one direction only but to do so, they have an intrinsic resistance to flow since the internal flapper needs to have something pressing against it to seal the opening.

A check valve would work well for something that generates enough pressure to open the valve, but the question is, does the Toyota distributor generate enough ozone pressure to continuously keep the valve open in order to ventilate it.

Apparrently not, as Toyota clearly had to go to rather extreme lengths in designing a complex VCV distributor ventilation system that would ventilate the distributor properly.

As to why is the summit check valve is being sold for a distributor, it may be that in their application, on a particular engine, the distributor is positively ventilated with a vacuum source, whereas on the 2F air cleaner, that is not the case.

 

[micruz60]

...another lesson at Cruiser Univ.

 

[FJ40Jim]

The dissy doesn't make any ozone pressure. If there was pressure, it would simply take the path of least resistance out through the cabin hose.

The small pressure differential between air cleaner and dissy would not be enough to overcome the cracking pressure on a conventional Ck valve.

There are other similar VCVs under hood on other cars that might be cheaper and more readily available, but I haven't walked the PnP looking specifically for one. Maybe something from Rockauto?

 

[cuencanolenny]

Thanks for the explanation Jim. But before I jump in with this higher expense, what is the advantage of using the electronic distributor on this tractor motor? Ignition points cost me $2.50 down here.

 

[FJ40Jim]

The usual: better spark, more accurate timing, waterproof, no maintenance...

 

[cuencanolenny]

Thanks Jim, guess I'll hang onto it and look into after the '70 is put back together.