When did Mack introduce this style of grille?

[james j neiweem]

Wasn't there also a two bar vertical grill

[Whiskymack]

On 5/5/2020 at 10:26 PM, Vladislav said:

All in all there's plenty of points in a Mack chassis which look simple at the first moment but when you start figuring it turns out many sized and distances differ between the models and production years. In many cases that's not really much but require clearing if you want to provide a correct work.

You are right. There were so many small changes made over the production run of each model. Just looking at the Western R's there were a variety of cab mounts, and other frame fittings over the years. This is what really piques my interest; finding the design differences and trying to work out the logic behind them.

I compared some Valueliner pics, pre and post Econodyne. Difficult to know exactly how the extra space for the aftercooler was achieved but this is what I think they did:

Moved radiator back a fraction

New hood hinge to push hood forward. (A lot of later Valueliners had a gap of about an inch or so between hood and cowl. I always thought this was to allow a bit of travel for air ride cabs but perhaps it was because the hood got moved forward)

Possibly a spacer between bumper and frame horns to push bumper forward but very hard to tell from photos. Would need actual trucks and a ruler!

 

 

[Vladislav]

On 5/7/2020 at 8:58 PM, Whiskymack said:

You are right. There were so many small changes made over the production run of each model. Just looking at the Western R's there were a variety of cab mounts, and other frame fittings over the years. This is what really piques my interest; finding the design differences and trying to work out the logic behind them.

I compared some Valueliner pics, pre and post Econodyne. Difficult to know exactly how the extra space for the aftercooler was achieved but this is what I think they did:

Moved radiator back a fraction

New hood hinge to push hood forward. (A lot of later Valueliners had a gap of about an inch or so between hood and cowl. I always thought this was to allow a bit of travel for air ride cabs but perhaps it was because the hood got moved forward)

Possibly a spacer between bumper and frame horns to push bumper forward but very hard to tell from photos. Would need actual trucks and a ruler!

 

 

Unfortunately (or fortunately) I haven't got myself into Valueliners. I really like the look of later RS/RL700 but currently just impossible to cover them up with complex attention. Now I'm really deep in my Eastern R600 and quite enjoy the entertainment which takes plenty of efforts. I think you're right on accomodating the CMCAC by moving the rad and modifying the hood. If you change the front end of a hood you could get more space for an aftercooler, reorganize the hinge setup and keep the look at the same time. As I noted from RS600 chassis pics with hoods removed (mostly posted by you) early and later models had front spring brackets and front engine mount crossmember almost different. So it just a different design with plenty of possibilities to install additional equipment.

Investigating my R-model chassis and also relating it to the MH one I noted that vertical (rail mounted) Neway lever brackets were attached to the frame rails with a spicer plate of nearly 3/8" thick on the R and with no plate on MH. Seems like those plates were used to compensate a possible thickness of the 2nd rail if the frame is double. you could also see such spicers where bogie torque rods meet the rails. There's a mounting bracket the rod end attaches to. And you can see such bracket fit on a spicer plate or just straight onto the rail. When you start figuring the way of possible use of the 2nd rails it turns out they could be installed inside with the main rails keeping their original distance between each other but in other cases it appears that when you put the inner rails onto crossmember's ends they would determine the position of the outer rails wider than they woukld be used as a single setup. And that means that all the outer frame brackets such for fuel tanks, battery boxes and even cab mounts would take different position. Seems really strange but seems they would indeed. A fact of the same matter is a chassis mounting Camelback stand. As you know its upper section consists of two portions of U-channel welded together with a center part. When the stand is in place the U's are inside the frame rails. At the moment I have 3 such stands, both in trucks and removed. One of them has steel stripes of nearly 3/8 thick welded along the upper and lower lines of the side U-channels where holes for mounting to chassis bolts are drilled. The rest 2 dont have them. The matter is the stand with the stripes was ised with single frame rails and the 2 without them were installed in double frames. Again, here it's clean you have spacers in place of possible inner rail and when the rail presents the spicers go off. But the story with airride suspension looks like the distance between the main rails may vary. And thats strange.

Also a miistery (I try to be short) is chassis differences between R600 and RD600 frames. They have different rail heigth (the same is between RW600 and RW700) What does that mean? That means that the rail lower edge seats on the front spring brackets . The cab mounts are attached to the rear ones of those. If so the upper edge of the rail must be closer to the cab floor than with narrower rails. But in fact it looks like it doesn't. This means that the sizes are compensated somewhere. That could be done by different brackets which difference you can't see by their look, or by higth of the front axle springs or by any other way.

Actually if you just drive your truck you don't mind such matters. If you restore an only and complete truck that also doesn't bother you. But when you start investigating ways of modifying or possibilities of use parts from one chassis on another a very patient attention is required to avoid unpleasurant missmatches.

Edited May 8, 2020 by Vladislav

[james j neiweem]

You have to be a Jack of all trades and master of some.

[Jamaican Bulldog]

When did this grille come out in the R and DM or U? I always thought it was the same as the one in topic until the responses enlightened here that it was different 

[Vladislav]

18 hours ago, Jamaican Bulldog said:

When did this grille come out in the R and DM or U? I always thought it was the same as the one in topic until the responses enlightened here that it was different 

This one was attached straight onto the aftercooler. So I expect it appeared together with it. Starting from 1984 I guess. The models are usually 688 and could also be 690.

[Vladislav]

On 5/6/2020 at 5:36 PM, james j neiweem said:

Wasn't there also a two bar vertical grill

Like this? More looks like it was a winterfront conteining two bars.

[Phase 1]

Looks like a bug screen.

[terry]

1 hour ago, Phase 1 said:

Looks like a bug screen.

That's what it is, used them for years.   terry

[Maddog13407]

our 82 R600 had the one like the pic i was referring to attached to the air the air. just a stainless thin look a like grille

[Vladislav]

16 hours ago, Maddog13407 said:

our 82 R600 had the one like the pic i was referring to attached to the air the air. just a stainless thin look a like grille

Lengthened R-model hood is described like starting from 1982. Does this mean that CMCAC took place starting from that time either?

[j hancock]

In 1982, the Tip Turbine (CMCAC) was beginning to be phased out and the ATAAC (air to air after cooled) was being used.  CMCAC stayed with the DM model for a while and steel noses for design issues.  No place to put the cooler in the front.

[Vladislav]

26 minutes ago, j hancock said:

In 1982, the Tip Turbine (CMCAC) was beginning to be phased out and the ATAAC (air to air after cooled) was being used.  CMCAC stayed with the DM model for a while and steel noses for design issues.  No place to put the cooler in the front.

Jim, isn't CMCAC a Chassis Mounted aftercooler? I always thought that and expected that attached onto the chassis in front of radiator.

[j hancock]

31 minutes ago, Vladislav said:

Jim, isn't CMCAC a Chassis Mounted aftercooler? I always thought that and expected that attached onto the chassis in front of radiator.

You are correct.  Sorry, I was talking on the phone on another issue while typing.

CMCAC cooler out front of the radiator.