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Pedigreed Bulldog
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Posts posted by Vladislav

  1. 18 hours ago, Rob said:


    I wasn't referencing the main headlamp switch but rather the toggle switch on the upper left dash by the windshield pillar. This switch will turn off the outer cab clearance lamps on the roof along with the tail lamps when pushed forward, and flash the bright headlamp setting when the toggle is pulled rearward. Both positions are momentary and spring return to center which is normal position. The toggle handle is much longer in length than the standard headlamp main switch also.


    Yes, that top left toggle switch with a longer stick was the 1st thing I got on my mind but I thought I figured that wrong since I knew it was for blinking by high beam. And had no idea it also does anything to the marker lights (and I still don't understand the reason to do that). Are you sure that PAI unit you mentioned is that longer handle one? More seemed to me it's another toggle swich which is located aside to the main one to switch the dash lights. That one has two positions - on and off.

  2. Very sad to hear. To difficult to choose words for such a case. Unfortunately we all are guests in this world and at a sertain moment the time comes to everyone. Good to a person if he or she was honest going over the life and there are people who are thankful for the things the person has done for them.

    Rest In Peace.

    • Like 1

  3. 1988 should have a steel hinge plate with a tube welded to put 3/4" bolt is as an axle and a bolled "rod end" which comes into the chassis bracket with its stud.

    From my experience I suppose you will need a new Grade 5 bolt of the required length with nut since it usually gets worn in the middle and that ball joint which is known as Aurora bearing and could be found. My copybook tells me I looked for Aurora MM-12 with 3/4 bore and 3/4-16 RH thread (and that's right) but I remember I ended up with a similar part (or exactly that one?) which had a grease nippel as an option.

  4. Those panels on Eastern and Western R's are completely different. Eastern ones are MUCH longer and I"m afraid (not sure) are less of the higth (narrower). Also Western parts were made of alu and had surface stamped by leaned lines which cross each other.

    Eastern panels were different as I said but what's important (to Eastern R owners) they were at least 3 (known to me) styles. Early ones were alu with four (some with six) holes for screws in the corners. The surface was of horizontal stamped lines combining polished and ground (sand-scratched) areas. Those were installed (as I could figure) on early hoods on non-CMAC trucks. The trucks with aircooler (longer hoods) purchased newer panels which were made of stainless steel. The same general design but as I was told by some owners of early R's those newer panels were less in size and didn't fit early hood opening really good. But that's not the end of the list. Later panels were of two different styles too. If you look at pics of Eastern R's you can notice some trucks had framings over the headlight openings in the hood and some didn't. I can't state those parts were installed from/to a sertain production year, more seem to me as an alternative factory option. Nevermind. The panels were different. Those which were used with no framings had four screw holes in the corners. And those which were supposed to be combined with frames had a sticking end at one side (toward the grill) to be slicked in below the framing and two screws in the corners at the outer side. And that is the style (and probably the only one) which you can currently purchase new. They're made by PAI and could be found on ebay etc. Part ## are FPA-5774 for the LH (with a square hole for pre-heater socket) and FPA-5773 for the RH (looking from driving direction) with no hole and you can use on the both sides if no heater to be installed. There's an issue if you're going to use those panels on a hood with no framings (as I did). First you need to cut off that sticking area. Than you find the two holes in the corners at the outer side don't correspond with ones in the hood. Seems like new holes were designed the screws to get into the framing not straight to the hood. And if you try to just put screws they get into the headlight opening not the fiberglass. So some kind of offset plates are needed to be made. And you sure need two more holes to drill at the grill side too.





    Mack Aluminum Trim 116QS456.1_resize.jpg

    • Like 1

  5. 18 hours ago, Freightrain said:

    Vlad, power assist was popular in the 60's even with cars.  The drag link had a control spool in it that controlled a cylinder to help steer.  The Air o Matic in trucks was similar using air.  I have it on my truck, as a simplier way to add power steering without all the fabrication work.  It has its downfalls, but I say better then nothing.  My unit was in good shape so I hope to get many years out of it.

    Like this conversation, even hydraulic power steering can have problems too.

    Larry, please explain me one thing. Do you have the Air o Matic in operation all the time when you drive or switch it on only when you need it such as parking lot maneuvering and so on?

  6. I never put my hands on a truck power steering gear so far but I have a couple of points to put in.

    1st. Once patiently stydieing description of design of Mercedes G-class steering gear which is too close to what was used on some Russian trucks of mid 60's I found interesting nuance about pressures. The matter was when you steered you activated some pressure in the box which was applied to a piston which moves Pitman arm shaft by some way to turn wheels. It's clear the harder the wheels to move at the time the more pressure you needed. Using that effect that pressure was also provided to some another part (piston or its area?) in the box so when you turn the steering wheel you have to put force against it. Telling different words the resistence of the steering wheel you felt as a "road feeling" was in fact not any force reacted from the road but a force simulated in the steering gearbox specially for the feeling. Sure there was a corellation but those forces were not the same thing. And taking that to account the matter of "blind" steering with some power setup could be in that very wrong design of the unit.

    2nd. Once I looked over design of early KrAZ truck powersteering which was an air assist I noted it had a power cylinder at the right of the truck and a drag link with a valve assembly at the left attached to a mechanical gear. Pretty sure I saw something similar on Western RL-model Mack but with hydraulic cylinder not air. Nevermind. The function of the system is you turn the wheel in the cab you move the drag link and there are control valves which are spring loaded by some way. If you drive down a highway or steer on ice just a few resistance goes from front wheels so valve springs don't compress enough to open valves. This means the power cylinder doesn't get any pressure so doesn't effect wheels to steer at all. And you steer just like (and in fact by) mechanical gear. As greater resistace to steer the road gives you the more force you have to apply to the sterring wheel. At certain point the force gets to the level of the valve spring to compress so valve opens supplying oil to the power cylinder and it helps. As long as you continue steering or even doing it faster the greater pressure gets to the assistance. If you stop sterring the valve spring looses application, depresses and closes the valve.

    What's interesting to us in that is an integrated power steering gear also has valves iside. And also has springs in those valves. Othervise it just couldn't figure when to start to assist. Mercedes G-model gear has them I know. So way to correct a power steering feeling is to play with the valve spring hardness. And not with fluid pressure or volume.

    Worth to admitt a man should be careful tuning a power steering. Since if you put settings wrong your wheels could start turning themself at some time. And they wouldn't mind you're standing parked or doing 60MPH down a highway.

    • Like 1

  7. In fact you can get them from Watts newly reproduced for $50 apiece any time which seems quite reasonable if you really need perfect ones for your truck.

    Watts made a really good job offering the most of the line of B-model emblems such as B-61, B-67, B-73 etc.

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