Exhaust bang bang bang

So I suppose my first step would be to find an old tach/tune-up kit/tool ...I guess I'll keep my eyes open at junk shops, garage sales and
fleamarkets?

Larry
--
Larry - Victoria BC -

1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
 
The banging in the exhaust comes from misfires cause by the charge pressure being too low to sustain the fire when the plug lights it. I can't
understand that the fuel quality could effect that at all. I guess it is worth a try, but I wouldn't get my hopes up.
Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
> The banging in the exhaust comes from misfires cause by the charge pressure being too low to sustain the fire when the plug lights it. I can't
> understand that the fuel quality could effect that at all. I guess it is worth a try, but I wouldn't get my hopes up.
> Matt

I'm with you Matt. There is no way I'm going to put some unnecessarily high priced premium gas in my rig. IMO anyone who thinks their coach runs
better or gets better mileage with premium is deluding themselves.

I'll check the idle speed first, soon as I pick up something to check it with ...I'll be looking for an old analog unit with a needle.

Larry
--
Larry - Victoria BC -

1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
 
> If you *want* to try it - there are a few other choices locally that are supposed to be ethanol free:
>
> Chevron 94
> CO-OP premium
> Costco Premium
> Shell V-Power 91
>
> https://www.pure-gas.org/index.jsp?stateprov=BC
>
> Rob
> 76 Royale Twin Beds, Dry Bath
> Victoria, BC

Not a snowball's chance in hell Rob, bloody regular is overpriced enough for me, I'll just run C0-OP regular like always.

Larry

--
Larry - Victoria BC -

1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
 
Mine runs great on the cheapest regular I can get...

Rob
76 Royale Twin Beds, Dry Bath
Victoria, BC

>

>> If you *want* to try it - there are a few other choices locally that are supposed to be ethanol free:
>>
>> Chevron 94
>> CO-OP premium
>> Costco Premium
>> Shell V-Power 91
>>
>> https://www.pure-gas.org/index.jsp?stateprov=BC
>>
>> Rob
>> 76 Royale Twin Beds, Dry Bath
>> Victoria, BC
>
> Not a snowball's chance in hell Rob, bloody regular is overpriced enough for me, I'll just run C0-OP regular like always.
>
> Larry
>
> --
> Larry - Victoria BC -
>
> 1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
> 6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
 
OK, I got myself an analog tach dwell meter. How do I hook it up? Was expecting to find a coil but it looks like I have a HEI system so the coil is
inside the distributor?

Larry

--
Larry - Victoria BC -

1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
 
If you'll look carefully at the extension on the side of the HEI
distributor cap, where the wire's connected, you'll see that there's a
second connection tab there, labelled on the side of the cap as "Tach".
Guess what...

Ken H.

> OK, I got myself an analog tach dwell meter. How do I hook it up? Was
> expecting to find a coil but it looks like I have a HEI system so the coil
> is
> inside the distributor?
>
> Larry
>
> --
> Larry - Victoria BC -
>
> 1977 Palm Beach 40,000 miles, PO said everything working but forgot the
> word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
> 6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
Ken, you sent this to the wrong Larry.=C2=A0Any questions, call my wife, Ze=
nna Schaffer at 1 360 888 7110.=C2=A0Sent from my T-Mobile 4G LTE Device =
-------- Original message --------From: Ken Henderson Date: 9/16/21 1:01 PM (GMT-08:00) To: GMC Mail List Subject: [GMCnet] Re: Exhaust bang bang bang If you'll look carefu=
lly at the extension on the side of the HEIdistributor cap, where the wire'=
s connected, you'll see that there's asecond connection tab there, labelled=
on the side of the cap as "Tach".Guess what...Ken H.On Thu, Sep 16, 2021 a=
t 3:54 PM wrote:> OK, I got myself an analog tach dwel=
l meter. How do I hook it up? Was> expecting to find a coil but it looks li=
ke I have a HEI system so the coil> is> inside the distributor?>> Larry>> -=
-> Larry - Victoria BC ->> 1977 Palm Beach 40,000 miles, PO said everything=
working but forgot the> word NOT. New Atwood fridge, water heater & furnac=
e. New SS exhaust system,> 6000w Onan, Iota Converter, R134A A/C, New fuel =
lines & heat exchange hoses> ______________________________________________=
_> GMCnet mailing list> Unsubscribe or Change List Options:>_______________=
________________________________GMCnet mailing listUnsubscribe or Change Li=
st Options:
 
Larry,

I'll bet (or at least hope) that the other Larry
(twlldeen) got it too.

Ken H.
On Thu, Sep 16, 2021 at 5:25 PM larry.schaffer
wrote:

> Ken, you sent this to the wrong Larry. Any questions, call my wife, Zenna
> Schaffer at 1 360 888 7110. Sent from my T-Mobile 4G LTE Device
>
 
> If you'll look carefully at the extension on the side of the HEI
> distributor cap, where the wire's connected, you'll see that there's a
> second connection tab there, labelled on the side of the cap as "Tach".
> Guess what...
>
> Ken H.

Good one Ken, I got the message no problem. The cap was pretty dusty and after I cleaned it off I could see the words.
I'd like to ask more about how to actually connect here and if I decide to install a tach in the dash, is this where I would tap into?

Anyway, before getting the answer about the tach take-off on the distributor cap, I'd borrowed a digital tach and stuck a reflector on the harmonic
balancer.
After she warmed up, my idle averaged about 720-740 in park so we tried bringing it down with the throttle screw adjuster ..... without success.
The screw backed off but the throttle cable/linkage didn't follow so I pushed the throttle closed and got her down to 640-660. Exercising the linkage
back and forth the stop was more and more prone to sit at the screw setting and finally gave the whole linkage/shaft/cable etc a good drink of
silicone lubricant which seemed to do the trick.

Putting her in drive, she idles at the high 500's with no sign of stalling or choking so maybe that's ok? Haven't been down any steep grades since,
but I'll report back after I do the next run.

Larry

--
Larry - Victoria BC -

1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
 
There should be 3 leads on your tachometer: +12VDC, Ground, and Signal.
Signal goes to that Tach connector on the distributor cap.

Ken H.

> > If you'll look carefully at the extension on the side of the HEI
> > distributor cap, where the wire's connected, you'll see that there's a
> > second connection tab there, labelled on the side of the cap as "Tach".
> > Guess what...
> >
> > Ken H.
>
> Good one Ken, I got the message no problem. The cap was pretty dusty and
> after I cleaned it off I could see the words.
> I'd like to ask more about how to actually connect here and if I decide to
> install a tach in the dash, is this where I would tap into?
>
> Anyway, before getting the answer about the tach take-off on the
> distributor cap, I'd borrowed a digital tach and stuck a reflector on the
> harmonic
> balancer.
> After she warmed up, my idle averaged about 720-740 in park so we tried
> bringing it down with the throttle screw adjuster ..... without success.
> The screw backed off but the throttle cable/linkage didn't follow so I
> pushed the throttle closed and got her down to 640-660. Exercising the
> linkage
> back and forth the stop was more and more prone to sit at the screw
> setting and finally gave the whole linkage/shaft/cable etc a good drink of
> silicone lubricant which seemed to do the trick.
>
> Putting her in drive, she idles at the high 500's with no sign of
> stalling or choking so maybe that's ok? Haven't been down any steep grades
> since,
> but I'll report back after I do the next run.
>
> Larry
>
> --
> Larry - Victoria BC -
>
> 1977 Palm Beach 40,000 miles, PO said everything working but forgot the
> word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
> 6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
> There should be 3 leads on your tachometer: +12VDC, Ground, and Signal.
> Signal goes to that Tach connector on the distributor cap.
>
> Ken H.

Thanks Ken. I'll have a closer look at the connector area with a mirror - is there an illustration somewhere as I don't see a tang there, is it a
socket that takes a plug pehaps?

Larry
--
Larry - Victoria BC -

1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
 
Forget changing fuel. The problem is not the type of fuel.
Just learn from John L.

> > There should be 3 leads on your tachometer: +12VDC, Ground, and Signal.
> > Signal goes to that Tach connector on the distributor cap.
> >
> > Ken H.
>
> Thanks Ken. I'll have a closer look at the connector area with a mirror -
> is there an illustration somewhere as I don't see a tang there, is it a
> socket that takes a plug pehaps?
>
> Larry
> --
> Larry - Victoria BC -
>
> 1977 Palm Beach 40,000 miles, PO said everything working but forgot the
> word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
> 6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
I did what he said Jim and set the idle lower. It was around 720-740. My idle is now around 650 engine warm in park and about 560-580 in drive. Is
that OK?

Larry
--
Larry - Victoria BC -

1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
 
http://rmcavoy.freeshell.org/diagrams/HEI/HEIconnectors.jpg

In the distant past - I recall just using a standard automotive spade connector.

Rob
76 Royale Twin Beds, Dry Bath
Victoria, BC

>

>> There should be 3 leads on your tachometer: +12VDC, Ground, and Signal.
>> Signal goes to that Tach connector on the distributor cap.
>>
>> Ken H.
>
> Thanks Ken. I'll have a closer look at the connector area with a mirror - is there an illustration somewhere as I don't see a tang there, is it a
> socket that takes a plug pehaps?
>
> Larry
> --
> Larry - Victoria BC -
>
> 1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
> 6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
> _______________________________________________
 
> http://rmcavoy.freeshell.org/diagrams/HEI/HEIconnectors.jpg
>
> In the distant past - I recall just using a standard automotive spade connector.
>
> Rob
> 76 Royale Twin Beds, Dry Bath
> Victoria, BC

Thanks Rob, yes that looks like it would work. On the hunt now for an accessory panel to mount a few gauges incl. a tach.

Larry
--
Larry - Victoria BC -

1977 Palm Beach 40,000 miles, PO said everything working but forgot the word NOT. New Atwood fridge, water heater & furnace. New SS exhaust system,
6000w Onan, Iota Converter, R134A A/C, New fuel lines & heat exchange hoses
 
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