JoeH
-
Posts
2,701 -
Joined
-
Last visited
-
Days Won
18
Content Type
Profiles
Forums
Gallery
Events
Blogs
BMT Wiki
Collections
Store
Everything posted by JoeH
-
I always figured they help with frame stress where the frame splays out around the engine and trans. My MR688 has 2 of those bars, one below, bolted to a bracket on the rear spring hangers, and a second one that goes across the top above the trans, right behind the engine.
-
38K Camel back leafs fanning out
JoeH replied to Bill 88 R 688 ST's topic in Driveline and Suspension
They are rubber/nylon bushing saddles, you can see the tube/bolt sticking out. Look for broken U bolt on the inside of the spring pack, down IN! the saddle holes. Our broken U bolt had rusted thin down inside the hole and thus the break was in there, where you can't see it unless you know to look for it. -
38K Camel back leafs fanning out
JoeH replied to Bill 88 R 688 ST's topic in Driveline and Suspension
The U bolts keep them from fanning out. I suppose you could have a broken U bolt, we did have one of those a couple years ago. But we also had broken springs develop on that same truck. The U bolts keep the springs sandwiched with thousands of pounds of force. The only way the springs could slop around is broken leaves, or stretched/broken U bolts. -
38K Camel back leafs fanning out
JoeH replied to Bill 88 R 688 ST's topic in Driveline and Suspension
I'll let your imagination figure out what happens when all 3 bottom leaves break and the one axle disconnects from the spring pack. Remember the springs "hang" from the axles, so that side will hit the ground. -
38K Camel back leafs fanning out
JoeH replied to Bill 88 R 688 ST's topic in Driveline and Suspension
I'd be jacking that truck up and cutting the u bolts to inspect leaves. After I ordered a new spring pack. And you'll want to do both spring packs at the same time, otherwise one side of the truck will ride higher than the other. -
38K Camel back leafs fanning out
JoeH replied to Bill 88 R 688 ST's topic in Driveline and Suspension
Those leaves probably are broken, the breaks are likely hiding behind the u bolts. -
Stock that engine should make 30+ psi of boost. If you were making less than that then I'd suspect boost leak. Our 95 E7-350 had dropped down below 25 psi, so we checked for leaks and found a nice long crack down the weld on the charge-air-cooler.
-
Did you lube the fuel filter O-rings before putting them on?
-
What's the history of this truck? Have you owned it long? Did you buy it with this problem? Did the problem start after having the brakes replaced? Joey may be on to something with that frame twist. Looking at it, it would appear the frame is twisted in such a way to apply the least weight to the passenger rear wheels. Typically trucks have ABS on the steer and the front drive axles, not on the rear drive axle. So your ABS would of course do nothing in this situation.
-
Any chance of swiping the oil pickup off the truck you're getting the pan from? I doubt the pickups are different depending on pan. Only differences I could foresee would be based on sump positioning. The pan and oil pump assembly can be flipped end for end depending on front axle to engine positioning, but I don't recall if there was a "center sump" oil pan.
-
My first though was compression ring, but that'd have a hard time getting out and dropping down. Looks like it's a bimetal piece, 2 separate colored metals appear to make up the piece.
-
I wouldn't mess with the filters. Leave it as is.
-
ESI (extended service interval) package is a 2 filter set up, 36qt oil change I believe. 32 qt pan, 2 qts per filter. ESI+ is the 3 filter setup. 6qts total in the filters, and about 50qts in the oil pan. 56 qt oil change, every oil change is more expensive, but you can go something like 25k miles between oil changes. It was an option for cross country tractors to increase uptime. For local/off-road I'd go with the smaller pan, better ground clearance on rough terrain and cheaper oil changes. Especially if you're not putting 50k+ miles on the truck per year.
-
Oil "level" is the same, so suction elevation should be the same. The deeper high capacity oil pan allows you to go further between oil changes, and is accompanied by a third oil filter, giving you extra filtration capacity for that extended oil change interval.
-
I'd bet a few bolts walked out, and the remaining bolt that stayed in finally had enough and snapped. Again, these bolts are supposed to have locktite, and the mechanic probably reused the bolts without putting any on. Certain bolts come from Mack with locktite already on them.
-
Having trouble seeing exactly what's going on with the bolts... One sheared off and the other walked out?... They're supposed to have locktite on them I think, so they can't walk loose.... if they walk loose they're subject to all sorts of fatigue as the engine/trans flex under power. It's not "normal wear and tear", I'd suspect it wasn't put together properly when the trans was replaced. We're getting ready to retire our 1979 mack, it has a trans bracket that keeps coming loose on the aluminum bell housing. 1 bolt hole is stripped out and the other 3 keep walking out.
-
Google Street View of the intersection doesn't show any low ground clearance signage, I'd be harping after the municipality and CSX that they should have had signs up with minimum ground clearance requirement signs. I've never driven a low boy, but I have seen ground clearance signs for exactly this type of thing...
-
The gal in the car summed it up about right: "oooohhh noooo....."
-
How many brake applications on a full reservoir?
JoeH replied to Old_DM's topic in Air Systems and Brakes
He probably has big brakes. Our 1980 dm686sx has 18"? Brakes instead of the standard 16"? Brakes. Truck always had great stopping power. I wish more trucks had them. -
Anyone else cringing that the company mechanic tightened down on that one valve not once, but twice?... @Joey Mack is beyond edumacated on these engines, it's crossed my mind to try to convince him to drive to PA if I ever have H ring issues on my 2003 ETECH.
-
The same gasket is used on the E7 motors as well as some ETECH motors. Bolt pattern is identical, you should have no problem getting one for it from your dealer. However I can confirm they're $2k, we put a new one on our '95 E7 a couple years ago. Note the PoS will have pin holes in it that require a newer style rubber gasket with tips on it that pole through to aid with gasket alignment. Some of these holes will leak oil if you try to assemble them with the old cork gaskets.
-
We also had a valve seat crack and drop into a piston on the same engine, where it chunked to bits and got lodged in the piston head. Damaged the head, ruining the core. It's time consuming, but if you don't find anything obvious with valve lash then pull the heads. Just don't set them face down on the table, the injector tips stick down into the piston bore.
-
Does it have Jake brake? If so, inspect the top of every exhaust valve for the disc spacer that rests on top for the Jake pistons to push down on. Our '79 endt676 has a weak valve spring on one valve, that disc kept popping out. We deleted the Jake brake after the second time it did it. I'd walk the engine round again slowly and feel for excessive valve lash. Carbide face may be missing off one lifter tappet, starting to wipe a lobe off the cam.
-
Did you lubricate the fuel filter o rings on assembly? Dry filter o rings could have bunched up, allowing it to suck air.
-
1979 R686ST This guy is likely getting retired in June while there's still something left to restore. Where do we get cab repair panels for it? Roof, sections around rear window, gutters.... Undecided if it'll get a 5th wheel or a coat of paint inside & out on the mixer body. My dad bought the mixer in 1976 on a different horse, and the truck in 1987 when the old horse died. Both truck and mixer are good talking pieces, & you'll be hard pressed to find an older volumetric mixer than this one. (It's a 1968 Daffin. Volumetric Mixers were invented around 1962)
BMT Forum Logo
