Harmonic Balancer

Hi All, Can anyone tell me if Inter 345 Balancer is the same as a 392 Balancer,

Yes they are the same, BUT the part number changed somewhere early in the 1970's for some reason, so you might want to try and be using/swapping a balancer from a similar age/era engine. I don't know what changed to require a new part number. The only thing i can think of is perhaps the balancer was modified to mount the cooling fan with the introduction of the tilt cab ACCO? That might affect your intended use.

Brett.

Thanks Brett, I have a slight vibration on Mobile 1 just above idle , when I lift revs it over rides it, I have not got to inspect it yet as far as the rubber cushion is concerned , I can get a used 394 one but was not sure about compatability, also I believe engine mounts can cause the problem just above idle have you heard this?, Kind Regards John.

Hi John, i would tend to think if something was out of balance the vibration would get worse with increased revs, not better? I guess that is not always the case though, i know many PTO tractor driven machines have their "sweet spot" where often another 50-100 engine revs will smooth out a vibration, so it's hard to know. I haven't heard of bad engine mounts causing vibration at just above idle, but it could be possible.

Just from my own experience with Inter V8's, i would put a new set of spark plugs in it first of all.

Brett.

Thanks Brett, When we bought Mobile 1 from a local Brigade they told me when they start her to turn out she carried on a treat, running like a chaff cutter so they revved the hell out of her and she came good until next time, I put new leads /plugs/points distibuter cap/ checked for vaccuum leaks/ ran oil along intake manifold to find any air intake to any cylinders/ fitted a heavy earth strap engine to chassis/replaced brake booster diaphrams (they had pin holes) but she still carried on when started cold,, until I remembered being told years ago when young , if you cannot find a miss or? at night with no lights lift the bonnet and start the vehicle and sure enough the ignition coil top looked like a lightning storm with the coil shorting through minut cracks in the plastic to ground ,new coil fixed, however she still has this very small shiver just above idle , I do know if the rubber in harmonics becomes cracked or oily the balance can change so that is why I will have to explore all avenues , maybe the dark night test may help someone else with hard to find missing. regards J.

used to be the rule V8 Inter 5,000 miles new plug and points.....I think electronic ignition improves the plug life ......a lot of the fire trucks had an electronic conversion of the old distributor.

I have read that people advise to try and cross plug leads 5 & 7 at 90 degrees, twice, to avoid induction. I have no idea if it actually helps anything at all, just something i have read.

Brett.

Never heard that....I always used the "combs" to keep the leads clear of the hot engine.........IHC numbered the cylinders different from any other US V8,and that used to stuff up a few mechanics....... what seems to be a funny firing order is actually the same as many other motors ......with a conventional cab ,always replace the plug behind the steering shaft,as there is a good chance it hasnt been done.

I have never bothered to try crossing those two plug wires, but i have read of it several times, and our local (now retired) old school IH mechanic has told me the same thing, so there could be something in it.

Brett.

I have never heard that Brett but will try as nothing ventured nothing gained, I apprieciate all the responses from all of you chaps , Thank You! Regards J.