[T2] Timing type 4 motor

[Greg Potts]

Hi Richard,

There's a lot to consider from what you have told us thus far.

If the engine/exhaust heat melted the cooling fan guard then you have a
problem. If the air going into the fan is hot enough to
melt plastic it's not going to be doing a very good job of cooling the
engine.

Is the engine tin and foam seal installed correctly between the
engine and the body?  Missing tin or a missing seal will damage your 
engine as the exhaust heat gets recycled endlessly through the cooling 
system.

With a stock type4 engine and a single-vac distributor I'd recommend 
running at 7.5 BTDC, and check the total advance to make sure it doesn't 
get any higher than 40-44 degrees.

I usually set all my valves at 0.006" and use a non-adjustable timing 
light without problems. I can't see a reason to retorque the heads from 
what you've told us but a basic compression test or a leak-down test 
would provide more insight as to what is going on inside the engine.

Happy Trails,

Greg Potts
Toronto, Ontario Canada
197x Westfakia "Bob the Tomato"
www.pottsfamily.ca
www.busesofthecorn.ca


On 4/23/2014 6:38 AM, Richard J wrote:
> Question about the timing on my 1974 type 4 motor. It has stock dual
> carbs, with a single vac. Advance distributor with points.
>
> My question stems from my road trip this weekend. My bus ran great
> until my second stop for fuel. It had trouble starting and staying
> running. I threw a timing light on it and when it was running rough
> at idle it was jumping from 8 to 12 advanced. If I revved it a few
> times I could get it run a little betterat 4 to 6 advanced. It jumps
> around some.
>
> So I emailed the guy and he said, "Glad the bus treating you well. I
> rebuilt the motor while I was working at danny's volks stuff, the
> summer before you bought it. New pistons and cylinders, new cam and
> SOLID lifters, all new bearings, ect. I used solid lifters because I
> hate the hydraulics. Set the valves like a beetle .006. I didn't do
> anything to the distributor, just installed the pertronix type points
> set up and made sure it maxed out at 38degrees total advance. The
> only way to set the timing is total advance, you don't really care
> what it's doing at an idle. You need an adjustable timing light and
> an accurate timing mark. Did you ever get a new timing tab? if not
> get one from bus boys." (I did get a timing tab)
>
> So, I replaced the petronix with points cause it went out after the
> first month I had the bus. Second I reset the valves at .006 intake
> and .008 exhaust. Now, ever once in awhile I get a pop when I start
> the bus that blows the small boot below the right hand carb, off.
> It'll start but runs rough. Once I push it back on it runs fine.
>
> So, the kicker is I ran the bus home pretty hard(lots of head wind).
> It ran great after I got it started, with advanced timing I talked
> about earlier. (I didn't think it ran too hot cause I could touch the
> dipstick and it was cool, and the distributor was cool enough I could
> hold my hand on it) After arriving home, I guess the exhaust or
> engine or combined melted the lower part if the plastic fan guard.
> Then before I noticed I started the bus(which started fine while once
> cool), and sucked in the guard parts into the fan.
>
> I can pull the motor and clean all those pieces out, but what about
> the timing? Valves? Torque the heads? I need a little help, please!
>
> Thanks for any advice!
>
> Richard Jack 1974 westy Lubbock, TX
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