Starter replacement on cat 775e dump truck!!!

[msllc]

How in the world do these starters get changed out? I've already replaced the one I was hired to do, but it was very tight & extremely heavy to lift into place while working at arm's length. I managed to use a small rope to lower the old one out of the way & hoisted the new one in place with a "make-shift" brake, but damn, that got tricky!! I am EXTREMELY glad that the job is now done, but I was VERY hesitant to do this job due to the expense ($1397) of the CAT starter & hefty mass & limited accessibility to replace it. I had to replace all of the battery cables (& BOTH batteries, too) on this dump truck, but that was a "cake-walk" compared to the manual lifting of that starter. So FLIPPING GLAD that it starts right up.

 

[Nige]

Another mechanic bemoaning the fact that the owner didn't opt for the air-start option rather than electric start. The air starter motor weighs about 12 pounds if my memory serves me correctly. Also the batteries in the air-start machine are only about half the size of the ones in the electric start model - another plus....

 

[Cmark]

The golden rule is don't hurt yourself.

In this business, components can be heavy and awkward, there's no getting away from the fact. If you can't do the job without a helper or hoist or rope or block and tackle or whatever, then just get it. What's your boss going to do? Change it out himself?

 

[kshansen]

Even changing the starter on a little 769C can be a fun job! Then add in the option of the prelube style starter and it's even better. What really bits the big one is when you have the new prelube starter in place to find out the new one has a -08 output fitting and the machine has a -10 pressure hose and it's a 90º fitting that won't clear the engine block with starter in place! At least I was able to loosen the mounting bolts and pry the starter away just enough to switch the fittings without taking it right out!

One of the best tools I had when I was still working was one of these:http://www.hoistandcranedepot.com/cm-series-602-mini-ratchet-lever-hoist-550-lbs-capacity/

That's not the place we got them, a local supply house carried them. That and a light weight nylon strap can save the day many times over.

And unlike the "helper" they might give you they don't need to take a ciggy break half way through a job or get distracted texting someone about last Friday's party!

 

[msllc]

A helper was not an option, due to being in a "highly secure" area. I no longer try to employ them. Most of them seem to only care about their personal lives or have some other major distraction in their lives. I got tired of paying them / helpers to watch me do most of the work, while they would still not soak it up, much less take any initiative . I ended up using a rope that was pulled taught with the winch on my truck. I was blown away that it WORKED!! I was happy that it did NOT have the pre-luber behind the starter. It did have a pre-luber mounted in front of the front axle, though. It felt GREAT to get that big truck to start, as I am the BOSS, of myself. So, I was thinking of getting a few small pulleys / to help hoist things into place easier. I will also say that this was the hardest starter to change, but only because I could not get close enough to the area where it mounts. Even if I could, I work still be working at at arms-length, with an 80 pound beast. I will say that the engine rotated easily after completion. I felt anxious before / while buying the starter (from CAT) & RELIEVED after it was bolted up. Ironically, there was a CAT-REMAN starter already on the engine, but the battery cables were just garbage; no heat shrink on the terminals, heavy corrosion in the cables, blackened / burnt copper in the cables, battery disconnect switch buried in dirt & rusted out and a ton more wrong with it.

 

[msllc]

 

[msllc]

 

[msllc]

The ONE thing that I REALLY want to point out is the second picture. Notice the two large (2/0) negative cables which were buried in hard packed dirt. I had to clean all of that out, because the battery shutdown / disconnect switch was so degraded that the switch could not be turned off in order to remove the key. That area is a huge design problem from CAT that allows the right front wheel to literally throw dirt into an open hole in the top of the compartment that is designed to shield the switches from that sort of hazard.

Notice the 5th picture how you can see the new clean terminals to the new shutdown / disconnect switch.

The very last picture shows the way the hard packed dirt was holding moisture & allowed the moisture "wick" into & up into the cables. That particular cable showed a 9-volt drop on a 24-volt electrical system.

Pictures 3 & 6 shows the rusting out of the switch body & corrosion that had worked its way into the starter "lock-out" switch.

I hope that nobody on here comes across a truck that has this many electrical issues. I was blown away by the shear number of how many there were in retrospect. fyi, this truck is for sale for a mere $320k; just imagine how this truck could be neglected this way, but worth so much money!!!!! It is baffling to me!!!

 

[mitch504]

I hear you about the "secure area", If you don't have a TWIC card, the ports here charge you $75/hr to be escorted by an off-duty Deputy Sheriff they are paying $15/hr.

I had to go on the Coast Guard base in Charleston, after hearing about how they are the reason for the tight port security, and when I offered my TWIC card to the Coastie on the gate, he said, "We don't mess with those things here", I and drove my tractor-trailer down the pier and parked 4 feet from a large cutter.

 

[kshansen]

msllc, If I didn't know better I would think you got the picture of that disconnect switch from the 769D I was working on the last month I worked before retiring!

Only thing is ours still worked. I was in the process of reskinning the front fenders that had rusted out. One of the problems on the right front of the 769D, and probably the same on the 775E is the right front fender is a major part that includes air filter mounts, steering oil tank mounts, and air tank mounts. What I did was use a 4 inch grinder with a cut-off wheel to slice it about a foot below the top and down the tubing that supports the lower edge. One of our loader operators has a fab shop and as he was on winter lay-off got the job of making a new skin with head light bucket and switch box. We then did a little trimming to make it fit nice with a slight over lap at the top and welded it on. Not sure how effective it was but I tried to seal the cover on the back of the battery box real good to keep the mud and dirt out.

I do like the pre-lube systems with dedicated electric motors. At least when they do fail you can by-pass the system and keep using the machine until you get a replacement motor of controller. And the newer machines actually come with the plug-in by-pass harness connected to them, that is if the guy who installed the system did his job. Our 773G did not have the by-pass or the labels telling you where they should be!

 

[msllc]

TWIC is EXACTLY correct!! It falls into that theory of "better to have it & not need it, then needing it & not having it!!" I am glad that I have had mine for almost 5 years now. I don't know a lot of people that can get a TWIC card / port id due to the background investigation. Other repair companies don't want to deal with issues of working on the ports, or even the nearby military bases. I know that when I had helpers a few years ago, most of them barely had a drivers license. I never had a single guy that had anything to go on to a port or military base.

I was surprised how open that battery switch box actually is, considering the amount of design & detail that CATERPILLAR generally puts into their products. If it was my truck, I would have installed a rubber flap to deflect dirt / water from entering that area. I would not say that it would seal it all out, but anything to minimize / alleviate that problem.

The "pre-luber" is actually brand new to me, but I understand the concept perfectly. This is the very first truck that I have ever worked on that has had this on it. I think it is a very interesting concept that must be worth having, or else they would not install it on the truck. I am curious what these would do in lesser sized engines. I would have to guess that it would minimize all start up wear due to a lack of lubrication. I really like the idea. If I ever build another service truck, I might design / install one on it. I cant see the harm in having oil pressure primed before the first crank on a cold engine.

 

[Nige]

I think it is a very interesting concept that must be worth having, or else they would not install it on the truck.

It's another attachment that the OEM can charge an even more extortionate price to offer to the customer.

Based on experience a prelub system is only worth installing for larger engines in machines operating in temperatures that are really cold and that have to start from cold every morning. Anything working continuous shifts doesn't really need it because they never get cold. Other than that it's just something else to go wrong. Any engine in daily use, even in cold temperatures, will not suffer greatly from lack of lubrication at startup so long as it is allowed to idle for a couple of minutes to establish full oil circulation after being started. You're right, there is no harm in establishing oil pressure before starting, but on the other side of the coin there is no harm in NOT establishing it either provided the engine isn't taken straight to high idle.

 

[Mark250]

i would not use the replacement toggle switch. it is not sealed and the connectors are exposed. The cat switch is sealed and the connectors are deutsch type which are also sealed . my two cents worth

Mark

 

[kshansen]

It's another attachment that the OEM can charge an even more extortionate price to offer to the customer.

Based on experience a prelub system is only worth installing for larger engines in machines operating in temperatures that are really cold and that have to start from cold every morning. Anything working continuous shifts doesn't really need it because they never get cold. Other than that it's just something else to go wrong. Any engine in daily use, even in cold temperatures, will not suffer greatly from lack of lubrication at startup so long as it is allowed to idle for a couple of minutes to establish full oil circulation after being started. You're right, there is no harm in establishing oil pressure before starting, but on the other side of the coin there is no harm in NOT establishing it either provided the engine isn't taken straight to high idle.

One thing I did like about the pre-lube systems was when doing a service/oil change I could install oil filters dry and then use pre-lube pump to fill them. Never needed it but also would work as a safety device if someone tried to start a machine before refilling crankcase. I always made it a practice to remove the key and either put in my pocket or clip to the clip-board the check list was on along with a tag out saying DO NOT START and 99% of the time I worked by myself.

A somewhat related use of the pre-lube is, on some of the newer Cat machines we had, this same pump could be used to pump the oil out of the engine and on the 773G you could also drain the hydraulic tank, transmission and engine all from one point. Just needed to connect an air hose to a valve on the inside of front fender. Two empty 55 gallon drums and 15 minutes all oils, less the front wheels and rear axle, were drained. To avoid cross contamination of the engine oil the last thing drained was the engine to flush out the system.

 

[msllc]

I agree that the switch is too open, but the customer is merely looking to sell it ASAP, so its what I could do the fastest & cheapest - FOR HIM! Keep in mind, that it works far better than that corroded picture of the old switch, though. Keep your fingers crossed that it sells ASAP. My marriage to it ends as soon as it is SOLD!!