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Tune up

PostPosted: Fri Jun 28, 2019 11:07 am
by Harvey
Do you tune your own? Valves , carb, VA , Dwell
What oil type , settings , just curious what others have done with their stock motors. No insults
if you don't like them stock thats good as for me I like em all but
I like dickering around with my stock engine and era tools of the trade just me ?

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Whats in your tool box ?
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☞ Fellow IH motor heads,
This SD240 engine is totally restored and mechanically correct.
☑New carburetor , vacuum advance generator and starter.
☑Valves, dwell , timing and VA are spot on:
☑Dwell 31 @ 750rpm
☑Valves @ .025 hot
☑Timed @ 7deg btdc
☑Manifold vac pressure16c 125' elevation at idle
☑6volt system all new stock including wiring
☑Motor oil Standard Shell Rotella.
☞ Thanks for looking and listening , be safe - sm

Re: Tune up

PostPosted: Fri Jun 28, 2019 1:42 pm
by Binder Mike
That's a big part of the fun for me with this hobby. These engines are so nice to work on compared to the modern stuff that's out there. Everything is accessible, the carb alone is a joy, I can have mine off the truck in less than 5 minutes.


Question? Is your truck 12 volts or does your tach and dwell meter work with a 6 volt system?

Re: Tune up

PostPosted: Fri Jun 28, 2019 4:01 pm
by Harvey
[quote]Question? Is your truck 12 volts or does your tach and dwell meter work with a 6 volt system?/quote]

Glad you asked , as I was going to post the information for my 12volt timing light.

The dwell & tac meter works on 6volt.
Now you did not ask but:
The timing gun is 12volts and can be used on a 6volt system as the strobe light works off the engines HV plug wires
but dose take an external 12volt battery hookup.
I was instructed some time ago to connect the 12volt leads on the gun input directly to a remote 12volt battery and then
with a separate wire connect the negative terminal of the 12volt battery to the trucks frame.
I have a brass terminal right on the front bumper for this connection.
Works great.
I use to know the reasoning for the negative frame hookup but it escapes me right now. There is much information and mis information on the
web in regard to a 12v timing light used on a 6 volt system , I go with what I was taught before computers..

Re: Tune up

PostPosted: Fri Jun 28, 2019 4:08 pm
by nikkinutshop
I like my modern vehicles. They don't need any attention other than regular maintenance. I build my old IHC with updated running gear so the required "work " will be less.
An old a analog meter, like the one in the picture should not be external voltage dependent.
Since you do your own work, maybe you could explain how a carburetor works? Someone on this forum may be wondering.

Re: Tune up

PostPosted: Fri Jun 28, 2019 4:19 pm
by Harvey
As I said the RPM meter works on 6volt as its a combo volt meter as well no brainer there right?
I would pose your question to the the carb guy on this form
elementary as it is you or another member would be better
served by an expert and since we have a resident carb guy
he may chime in for you. and others..
I can set the idle and adjust air flow for the va with ease & correctly
using the Vacuum gage and RPM meter. A seasoned mechanic also uses
his ear , that of course comes with experience.
Even a seasoned shade tree mechanic like me can get a feel for the
sweet spot and how sweet it is :)

take care-sm

maybe Mike can help you with your carb question

Re: Tune up

PostPosted: Fri Jun 28, 2019 4:53 pm
by nikkinutshop
There are two vacuum sources. Which one do you use?.

Re: Tune up

PostPosted: Fri Jun 28, 2019 5:09 pm
by Harvey
Right there are two..

Let someone else be the irritant for a change will ya, just kidding :).
looking forward to seeing those leathers your making.
Were not talking chafes folks - lol

Re: Tune up

PostPosted: Fri Jun 28, 2019 5:17 pm
by Binder Mike
Altitude plays a big part when it comes to reading manifold vacuum, you get a considerable drop for every thousand feet above sea level. I live at 7,700 feet in elevation and pull about 19 psi on my motor, not bad considering how high up I am. I also have lean the carb out a little bit and slightly retard the ignition for those conditions.

Re: Tune up

PostPosted: Sat Jun 29, 2019 1:31 pm
by Harvey
A couple obervations and tips.

For those who choose like me, to keep it 6volt , start with proper size conductors and solid electrical terminals and connections right at the starter. You won't be disappointed . Rate the wire at least 1/0 with copper lugs. I prefer bolted type but crimps are fine when done properly.

And don't overlook a good ground from the battery directly to the generator , there is a reason the Generator has a 1/4"Threaded Screw Hole on the frame. Mine even had a ground symbol on it..

Also there is an overlooked item on the firewire near where the steering shaft passes through, you will find a Factory Marked Grounding Point NOT to be confused with the other small one at the firewall with wire that is near the top of the engine on the left side. Usually factory connected to the engine head.
The one I speak of will provide a better cab ground for dash lights and gauges.
(I find it rather strange that this symboled factory cab ground was not used, could it be only on the R112 cabs ?? Doubtful but, I hope some one checks theirs for this and chimes in)

This is all for the novice if a pro wants to chime in please do. but refrain if you have nothing constructive to add. It just muddies up a good start to a conversation.
Spelling and grammar to be excused.

I like dickering around with my stock engine and era tools of the trade just me ?

Re: Tune up

PostPosted: Sun Jun 30, 2019 4:56 pm
by Binder Mike
So what is your dwell setting and at what rpm?