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Which bolts do i take out, the four that go in vertically on the block that attaches to the accesory drive? And i belive i need a gasket too?

yes to both.

Just reading some other econovance posts and i see there are some screens in the econovance block. My truck seems to take FOR EVER to clear up in the morning. Just replaced braided line that feeds oil to it. I am wondering if these screens could be the culprit. What is the original purpose for these, and is it possible that they are acting as an orfice and not imediately allowing oil to get to my econovance solenoid? Are there any reasons NOT to remove them? Please tell me more....

97 CH613 400(+30% w/ blixxton box),835K miles

Take them out! if you bought a new econovance today they do not have screens!

hello to all my doggy brothers and sisters, i've owned my gravel granite since new(2005) this bleddy 460 has been given all the latest and greatest program/software upgrades and i still am suffering with the truck..... well almost stalling with a full legal load on even a 5% grade(incline) off the line. My warranty is over now and i'm wonder if anyone can tell me if there is anyone in the vancouver,bc canada area that knows how to fix this(AND NO!!! THE DEALERS DON'T EVEN KNOW) otherwise i gotta take the trailer off and run it single.????????????????? FELLOW DOGGY

ya a few tips on this he has done a few tweaks on his unit it seems to have him happy.

I have a 1986 R688ST Tandem Axle Dump Truck. I am looking to figure out what the problem is with my brakes, but the air lines are the biggest jumble of a mess i have ever seen, and I don't know where to start on this one. There are two things I would like to address here...

1. I don't know where to start on this one, but the brakes just aren't as good as they ought to be (haven't been since we purchased the truck 5 years ago). I put all new drums, cans, and shoes around the truck, and a new valve under the pedal, but it just doesn't stop like it should. Anything else to replace that would help?

2. I believe this may be a road tractor conversion, but all the tow lines have been capped off in the frame rails. I would like to tie the hand brake into the brakes of the truck. How would I go about doing this? Is it best to tie into the front or rear?

Any help to this would be great!

I highly reccomend a place to start is Any Big line from an air tank to the bottom of any or all relay valves first.I have seen lines degrade over the years and cause your exsact symtoms!

Ok, that is what I thought. If you read my post up top, then you know the problem I am having. Was wondering if you knew approx. how much a harmonic balancer costs? It sounds as though I am going to need to replace that from what was about the other person having the same problem with their truck and it ended up being the problem.

Definate possibility on that balancer, I never ran into that problem on a mack , but I did on a binder dt466 kept throwing belts tried everything with that too, then took a stab in the dark with the balancer which cured the problem!

You wouldn't believe how clutches are set at the plant lol....how do you guys set them? I know how I set em.....I'd like to know how much variation you guys get from the plant too thanks

Iv'e seen em come to our shop decked straight from the plant with as much as 2 inchs of clutch brake and the correct free pedal! That would mean that there would be MAYBE 1/2 inch of clutch gap between the throw out bearing and the brake surface! More often than not there is 1 inch useually that is the case that is still too much with an air assist clutch in my opinion.We ussually end up tweeking the clutch brake before delivery to fend off clutch brake desasters with the mp engines as I dicribed earlier!There is nothing wrong with the eaton two peice clutch brake as long as you install it with a wad of grease on it and set it real light they will work for a long time!The volvo people wanted us to put one peice brakes back in at one point!

Hello everybody,

Mack build some trucks with Scania engines, but What type? what year? and how many?

Best regards

Erwan

for ever

They were RD,s or RS's models back in the late 70's/ early 80's Not sure on the volume of trucks, back then they offered all engines . scania ,cat ,cummins, detroit I even seen a Man in one but I beleive it was a trans plant!

Thanks for the info. Couple of questions? First, you said the the fan weight on the hub can be changed. Was wondering if you could elaborate on that. Do I get a different model or do the new fans just weigh less.

And second, do you know how I would find out if my particular truck calls for that bracket. The guy at the parts place I go was kind of unsure.

Thanks

No Bro I said , hub itself weighs a ton thats the rest of the problem but you can't change that,Get a new fan an check to see if the upper bracket is missing!I am not sure on your truck either but if there is a nub sticking up on the housing with a threaded hole in it it is lkly to have a bracket on it!

with my muffler i can use my engine bracke a lot more than with straits. and i hate to use my brakes. i feel like it cost a hunert bucks every time you touch them. im trying to get 500,000 out of these.

yup thats true the brake does come thru load and clear!

do you have to remove the knob???????????????

post pics???????????????????

Chuck no pics man sorry! If yours is mack 13 you can chance taking the knob apart theres a lock out in there that interlocks the two switches ya just got to cut or break it off I beleive its Plastic!

Got your PM thanx Has!

Found IT! http://www.bigmacktrucks.com/index.php?app=tutorials&article=43

I hear you there!

Got your PM thanx Has!

i would love to straitpipe mine, but colorado would like the revenue

We done several here and the noise factor aint bad once the egr valve is closed the noise is not bad.The white one you guys were ooing and awing over a few months back was straight piped I beleive.

Interesting. So do you mean it might be possible, or might not be possible?

I know it's shown in the TS494 manuals.

No Bro that stuff is to modern !This here was an oldy but a goody.I beleive the new stuff is V tainted, this was a grass roots straight forward ,proper way to adjust the clutch on a mack with a simple clutch cable no air ass/ sist junk on there type clutch.

I have seen improvements in power on certain CX style trucks that had the muffler underneath the cab/sleeper. That style muffler seemed very restrictive. A straiht pipe was put in place of the muffler. The truck wasn't to noisy but the dual exhaust was behind the 60" sleeper and had tall pipes. A friend has a 2004 CV dump truck with a AI-427 and had all custome exhaust from turbo to exhaust tips. He had squeezed 5" pipe starting at the turbo ( hard to do in a CV, you now have to remove the turbo pipe to get at the #5 and #6 EUP) all the way to a 6" TEE then 6" dual straight pipes in place of the mufflers. It did run better but you couldn't listen to the raido or cell phone while goin down the road. After about 6 months he replaced the straiht pipes with mufflers but left the larger turbo pipe and Tee and said it still ran better than stock.

We are talking AC 460 Right?there are possible gains on older riggs! pre 2004

I was wondering, what the effect on the performance of my 460 would be, if I did away with the muffler? I think I can try it without taking the muffler off and if I don't like it or it's way too noisy, I can go back and hook the muffler up again. Will my MPG go up or down, will it performed better? If anybody can help please let me know

Thanks

Larry

No performance gains to be had, not to bad for being noisy if the exhast is behind and above the cab!the turbo and egr valve take care of the noise for the most part!

several years ago before the format changed here there was a tips and tricks kinda post on how to set the clutch it was in the wiki portion of the page !It was a Mack TSB letter head it was posted by one of the members here I'm tring to find a copy of that TSB or Helpfull tips , (service Hints ) or ( what ever)! It discribes setting the clutch in the proper order checking and setting the clutch brake first then doing the internal adjustment.

Does anyone have a copy of this????!

Thanx!

Hey Everyone,

Need some help here before I put a bullet in my head.

I am having an issue with my water pump. Its a Tri Axle Dump 97 Mack RD688S with a E7 350. Last six of Vin is 032419 if someone has any diagrams.

Ok, I drove the truck for about 1 1/2 months then my water pump went. I noticed over a period of about 2 weeks that the water temp. was reading hotter and hotter later in the day until it finally went real high and the temp light came on. So I got a replacement pump and put it on.

Ok, here is my delimna. It was about 1 1/2 weeks ago that I put the new pump on. The pump mounts on 2 places. It mounts with 6 small bolts on a housing on the front of the engine. Then there are (2) 12MM bolts that screw on the drivers side of pump to the oil cooler. Well the day after I put it on, about 7 hours after hauling, the bolts had backed out enough that antifreeze started spewing out of the gap where the pump and oil cooler come together. I saw no reason why this should happen but took the bolts off and replaced the regular washers with lock washers. Went the next day and about the same amount of time as before, it starts all over again. Bolts again backed off enough that it started leaking again. I took the pump off and checked the pump. Also had a mechanic friend come over and he said pump looked perfectly fine. We cleaned it up, put new gaskets with the high temp. permatex with new gaskets. Put the lock washers back on and also added Locktite to the bolts. Again, today it happened again only this time it cracked the heck out the housing the pump bolts on. So now I have to replace the housing.

The clutch fan that is on it, one of the blades has 2/3rds of it missing. I asked the mechanic if that is enough to throw it off balance and possibly be doing this, he said he highly doubts it. He also said how would it have lasted all the time without leaking before replacing it. I am going to replace it anyway.

So, I am trying to figure out why those 2 bolts keep backing out. There has to be somekind of vibration that is doing it, I cant figure out what else would be doing it.

Anyone have any ideas. The guy at the parts store said he thinks there should be a bracket on there but I dont have any schematics to check and see and he was not sure as the computer did not show one for my year but he thought it did have one for my year. He also told me that they did away with the small bolts that mount onto the housing. They use the same size bolts, but now they have longer bolts with a spacer. I asked if the small original bolts could have had anything to do with my problem but he said not likely since it was the 12mm bolts that were backing out.

I need to get this problem fixed so I can stop losing work. Any help appreciated.

The longer bolts with a spacer is an update as the bolts used to break on some models! The fan blade is likly most if not all of the problem here youalso notice the fan hub itself weighs a ton thats the rest of the problem but you can't change that,So My bet is the fan blade!also on some models there is a 1/4 inch metal bracket that bolts to the corner head bolt lh front of the engine if that bracket is missing this may add to your problem.

Yup its true !you can also modify the 13 knob to make 18! by breaking off the lock out tab!

There are parts available to change it over to the standard type clutch cable.

Highly recommended I might add!

On the newer engines these have caused a lot of greif!

These rarly come adjusted correctly from the factory They tend to take out the clutch brake which then wipes out the sensor on the fly wheel housing two or three times before you get all the peices .

The sensor is Not a nice thing to change.

Funny thing is they blame the clutch brake when the real problem is the clutch adjustment.

Delete the air doins and get back to the real clutch cable!

wreckers around here are legalized rape nowadays. Most get $350 for hook-up plus minimum $5 per mile on long pulls. On short pulls they get anywhere from $125 to $300 per hour plus the $350 hook-up, if they pull the trailer with you it goes up from that.

a few months back I paid $750 for a 275 mile tow and thought he cut me a deal. He didn't wrecker it-- he brought a double drop and hauled me in.

Yup and notice there all driving older reliable rigs?!!!!!!!!!!!! Hummmmmmmmmm! Whats up with that!

AC--The tech lied to you because Speedco is supposed to change ALL filters. Maybe if you ask a shop manager to stock the filters they would accommodate you that's what I did and Speedco and Truck King--Houston both started stocking them. I keep a new centrifugal in my toolbox just in case.

When I'm in a bind and need a service job sometimes I use Petro or TA truckstops. If they don't have my filters in stock they go to the parts store and don't charge me a service call for going to get them.

I beleive you can buy them thru NAPA as well.

>If you have one that has been on the engine for a while take it and cut it open and you will be amazed at what you find inside of it. <

Amen to that! Yet Another great Mack idea done away with by the Volvo people!

yes sorry for getting back so late.Truck is like a homing pigeon just keeps coming back for different things.Found the turbine to snap off the shaft blocking the exhaust.Strange that the compressor side felt normal,[no play,and spun freely]Couldn't even pull the shaft for excess end play.Now i'll check both sides on the turbo next time just for this reason.It was a reman turbo right from mack only lasted 8 hours.The dealer said he had a bunch back for the same reason including volvos.One of the new uni pumps started leaking at the flare where injector lines seal.Tried a nother new line and 2 old ones still spraying had to replaced uni pump with another.It would have to be #6.At least the customer was understanding and knew it wasn't due to the service just faulty parts.

Good find ! I'll be watching for this too!