Aims -
Strip down the truck through the winter as it is less likely to be used at that time.
restore outer wings (fenders), front grill, and bumper removed.
Refurbish and improved air conditioning and heater with all pipes hidden.
Tubular suspension to be set up for best handling, castor, camber and tracking.
Front wings to be restored and painted.
Fit new (triple plated) chrome front grill.
Moving the air conditioning drier.
Since the firewall was now "clean" a new air conditioning kit was chosen and the drier in the new kit was fitted to
the front of the condenser using the special pipes provided. Custom made steel brackets were designed and
fabricated to hold the condenser onto the radiator support frame. Again stainless steel bolts were used.
(The drier had originally hung on the firewall and so this all contributed to a clean firewall.)
Moving the air conditioning and heater pipes to produce a clean firewall is detailed below.
Feb 2011. Quiet Mufflers (Silencers).
The front end strip down was interrupted for a couple of days to produce two new bolt on mufflers.
As shown previously, the design we have is a 3-part exhaust system using stainless steel flanges.
The same jig was used as per the previous mufflers. A local "laser profiling" company was used to
make the 4 flanges - £10 per flange (about $15 per flange). The mufflers are "Walker Quite-Flow 3"
units - part number - 22623 from Summit Racing at $74.95 each. Summit part number WLK-22623.
2.25" to 2" adapters were used as pipe spacer / adapters. These mufflers are ideal as they are
very compact (11" long) and have a low profile (3.25" high). They are designed as OEM equivalents
for an Oldsmobile Cutlass (1983-1987) with a 5.0L V8 engine. Clearly these are not "Hotrod"
performance "Flowmaster Hushpower" mufflers like the those already fitted, however, since this
flange system enables the mufflers to be changed over in about 20 minutes, this quiet set can
be fitted for the long distance high speed trips. With other modifications we hope to be
able to hear the radio at 70mph! Already fitted is a large amount of cab sound deadening
(although not including the doors as they have not yet been restored). We intend to removing
the rain gutter around the top of the door to reduce wind noise and eventually a 4-speed
automatic transmission (including an overdrive gear) will replace the "Turbo 350" to
reduce engine revs at high speed. Everything eventually adds up to reduce overall noise levels.
Update 2020 - The sound from these Walker muflers have always been fantasic and they have never been removed.
March 2011 - Continuing front end modifications.
March 2011. New pipe entry position. Fitting a pipe bulkhead manifold.
To keep the firewall as clean as possible, the two air conditioning pipes and the two heater
pipes enter the cab just forward of the left hand door and under the outer wing (fender)
using a bulkhead manifold. The pipes are also routed and concealed between the inner and
outer wings (fenders). This minimises the number of pipes being visible in the engine bay
March/April 2011. Fitting a powerful heater.
The 15000 BTU Maradyne fan heater was purchased from www.maradynemobile.com
The chosen position was against the trucks original ventilation louvers. Here there is a removable inside panel
fitted with 6 bolts. This panel was removed and since it is original GM, it was stored and a new panel
manufactured of the same dimensions. A hole was cut into the new panel and the heater fitted over the hole.
Fresh air from outside enters the heater matrix (see pictures below) and then there are several options.
If the (hot) water valve (switch) is closed, fresh air ventilation will come through the heater without being heated -
1. By a small amount of ram air (fresh air forced through due to the truck moving forward)
2. Adjustable fresh air ventilation due to the three speed fan.
If the heater valve is turned on and hot water flows through the matrix -
1. Heated ram air (a small amount of air forced through due to the truck moving forward)
2. Adjustable heated fresh air ventilation due to the three speed fan pulling the air in.
By fitting the fan heater directly onto the new cover plate, no ducting was required and this is quite
an easy modification. Once again it is totally non-destructive as far as the truck is concerned as
only original holes for the original cover plate were used.
The pictures above show the routing of the pipes through the Vintage Air air conditioning unit, however, later (see below)
it was decided not to route the pipes through the air conditioner (which is also a heater) and only route
them through the heater and out through the bulkhead. The truck heater provides enough fresh air heat.
A temperature controller was also fitted. This consisted of a rotary control (with knob) in the cab, a control
module and a temperature controlled valve also in the cab under the dash. The module being attached to
the firewall and the valve in the pipe from the bulkhead leading to the truck heater.
The unit used is a Vintage Air "Servo Heater Control valve Kit" Part number 50507-VUA
This kit includes the rotary control, the valve and the ECU control module and costs $89.00
Available from "Summit Racing" and many other dealers.
The right hand knob above is the fan speed 3-way switch which comes with the Maradyne truck heater.
The second knob from the right is the temperature control which controls the water flow through
the heater valve and adjusts how high a temperature you want in the cab.
The left hand two knobs are for the air conditioning.
The result of all of this, is that large quantities of heated fresh air are dumped around your feet, exactly where it is needed.
Update March 2020 - . Notes on the "heater plumbing" are detailed on the "comprehensive cooling package"
added to the truck in 2019 and 2020. Also see, on the same page, the "cooling system plumbing" notes as well.
2020 Update. Heater and coolant plumbing.
When the water pump is turning, the top of the engine and radiator are at high pressure and the bottom of the
engine and radiator (and pump) are at low pressure. Fluid flows from high to low pressure. Since the pump is
at low pressure, every side port in the pump "sucks". It draws cooler coolant from bottom of the radiator and
it draws cooler coolant from the heater. Many pumps have a large port for connecting to the bottom hose and
a small 1/2"NPT port to connect to the heater. If there are two small heater ports on the water pump, either
can connect to the heater. They are simply there to give you two options on where to connect the heater pipe.
Once you have chosen the easiest pipe routing, the other small port (both will be 1/2" NPT) can be plugged
with a (1/2" NPT) plug. The part of the pump in contact with the engine usually has two outputs to pump cooler
coolant into each bank of the V8. The top hose returns the hotter coolant to the top of the radiator. A port
on the top of the engine / inlet manifold, also sends hotter coolant to the heater (via a temperature
controlled valve). The radiator extracts the heat with ram air and sometimes with fan assistance.
The heater extracts the heat with fan assistance.
April 2011. Making the air conditioning pipes and heater pipes.
The tool, pipes, fittings, condenser and dryer were purchased from www.nostalgicairparts.com
The tool was $200 (Part number: TZ1007) and worked extremely well. The compression tool was designed to be
held in a vice but since many of the pipes were cut and set up "in situ" so that exact lengths and alignment
were possible, it was found that a pair of Vicegrips and 3 pairs of hands worked well. (The first end was
fitted on the bench and the second end in situ for exact lengths) Clearly taking the pipes and fittings
to a commercial pipe fitter would have been much more expensive than buying the tool. Also when you do
the job yourself, plenty of time is taken to do everything correctly for perfect routing and quality.
Update 2020 - Later in 2019/20 as part of a "comprehensive cooling package", the compressor was changed
to a very attractive Chrome Vintage Air Sanden 508 compressor (as part of a 2020 engine dress up package).
Once again the tool was used as the pipes going to the compressor needed the end connectors changing
from 180 degrees to 120 and 135 degrees.
The 135 degree fitting (above left) came from "JEGS" via ebay at $11.49 part number ("Vintage Air") 35842-VUG
The 120 degree fitting (above right) came from "acpartsguys" via ebay at $17.95
The compressor has 2 ports -
The 10AN female O-ring Beadlock fitting is for the low suction port
The 8AN female O-ring Beadlock fitting is for the high suction port
The 10AN (5/8") fitting with 7/8-14 thread size is for #10 1/2" ID and 1" OD barrier hose.
The 8AN (1/2") fitting with 3/4-16 thread size is for #8 13/32" ID and 29/32" OD barrier hose.
July 2011. Air conditioning vents.
The air conditioning unit also contains a heater and the hot or cold air comes out of the new circular dash vents, the demisting
vents and the below the dash vents. This is a re-circulating system. Fresh outside air and heated outside air comes through
the extra heater that is on the inside of the external louvers and is detailed above. (Also see picture) A computer
controlled water valve now replaced the switch valve so that the amount of hot water could be infinitely variable as it
flows through the pipes into the cab. This provided an excellent variable temperature control.
The 3 speed fan on the air conditioning / main heater is separately switched to the 3 speed fan controlling the extra heater.
There is also the mode switch and the variable temperature valve controller knob. Shown in the pictures is the compressor
with U connections taking the pipes directly down to the chassis. Also note that everything is neat and largely hidden
through the inner wings The pictures above also show the routing of the air conditioning pipes through a manifold at
the right hand side of the truck, forward of the A pillar and along the inside of the inner wing. The blue heater pipes
(and copper pipes) route along the inside of the chassis. Later insulation was wrapped around the copper pipes.
All of the outlets and control knobs came from "Vintage Air". They were a good match. The circular outlets
and the chrome finish matched the original dials and chrome in the truck.
Update As stated above in the "truck heater" section above, later it was found best to only use the vents for the air
conditioning. The truck heater is powerful and routing the heater pipes through the "Vintage Air" unit was not required.
July 2011. Painting the front wings (fenders).
To paint the front wings, they needed to be removed, and this resulted in another front end strip down. The wheels, front
bumper, front grill and hood slam panel all have to be removed. The lighting cables must to be disconnected and the
radiator loosened on it's mounts. Then all of the bolts removed. The wings were media blasted, repaired with new
metal where required, either welded or soldered. A small amount of welding was need in one corner and holes were
filled with new metal and solder. They were then etch primed, prepared, filled, rubbed down primed and eventually
painted with top coat. They were re-fitted just in time for the "Rally of the Giants" show on the 30th July 2011
This show was a 250 mile drive each way. As usual the truck was driven and it drove there at high speed without
problems and was reasonably comfortable. Relative compared to the way it used to be but still with room for
improvement. There was not time to remove the gutter rails to reduce wind noise at 70mph but this would be
one of the next jobs. Improved tyres to improve ride and road noise were also planned soon. The weekend was
hot and the new air conditioning vents worked really well. The previous narrow vents did not throw the air
onto your face but the new large circular vents worked perfectly
Update 2020 The truck was painted to a very high standard in 2016, however the important work done here
made the re-painting in 2020 and much easier job.
The last picture above shows the truck at the "Rally of the Giants" show one day after the wings were re-fitted (in 2011).
It was parked in front of Knebworth House in Knebworth Park after the show so that pictures could be taken.
Also note the whole truck was painted to a very high standard later in 2016.
Update 2020 It is planned, hopefully in 2021 to return to the excellent setting of Knebworth House and take new pictures.
August 2011. Wheels and Tyres.
A whole page has been dedicated to this subject
Click here for "Wheels and Tyres".
