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97 4L80E dropping out of TC lock up

back in business....

guess what, my bleeding off fuel pressure is gone too, who would have guessed that?

i should not have pushed the bleeding fuel pressure towards dead check valve /pressure regulator like forums kept telling me...
 

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WarWagon said:
Go ahead and waste your time and money rebuilding the trans. The rebuild can last exactly 30 seconds slipping before it burns a clutch pack up from slipping if you don't catch the problem. New parts don't mean good parts so if you introduce a second problem it gets more fun.
Click to expand...

i don't "fix" stuff on suggestions or suspicion... i dont fire the parts cannon, unless its common, cheap, fast and contrary to that proving the failed part is a PITA.

what i do is diagnose the faulty part and then go from there, hence why im so allergic to trans specialists telling me to do a rebuild. if its an outside of trans case issue, the new one would be a DOA too.

and if i need to rebuild anyway, driving a while in 3rd wont do too much MORE damage....

WarWagon said:
The Overrun clutch for manual 3rd is a weak point. Doesn't take much to burn it up.
Click to expand...
what do i need to avoid to not burn up the 3rd overrun clutch?
WarWagon said:
You are taking the grades too fast and/or too heavy if you burn the brakes up.
Click to expand...

no my friend, i took a 21k lbs motorhome that was built on a 15k or so Chevy chassis, that has factory brakes that are renown for dragging, out on mountain grades with at least 25 year old dot 3 in the system and a non working tag axle brake that was supposed to take up 8k of those 21k.

missing over 30% of your capacity, old fluids and dragging calipers is a real bad combination.

last time i came down pike peak, the ranger checking brakes mid way, went to get an other thermometer because she thought hers was broken... im a German, we know how to drive.

today i did Vancouver Whistler Merritt Vancouver. a 740km / 450 miles round trip, mostly though steep mountain grades, look it up, you probably can count on two hands my brake application. and my average fuel consumption over the whole trip was about 30% lower than the 5000km average of the car i had. 11,7 ves 9.1 L/100km, but i was mostly the fastest on the road, a road ive never driven before.

i do know how to drive, like most Germans do, we need to, with no speed limits on the Autobahn, if you don't you end up as road kill.

but no matter how less you touch the pedal, if the dragging calipers make the discs starting to crack, you wont need much to have wasted brakes. and the other conditions didn't make it better, now did they.

hence why i did a full rebuild on them earlier this year. before we started into the next season. both masters, hoses, calipers, pads and drum assembly. on the front new bearings and discs and abs sensors too, on the drive i haven't had the opportunity jet to replace the disc's, no clean environment to open up the axle.

ever since no break problems, even on the steep roads around Telluride and in the Sierra Nevada and Yosemite and Sequoia NP...

i also now know how to use the 454 as engine brake, wired up a kill switch to the injectors, so that i actually can have it pump lots of air at wide open throttle, compared to idle injector cut off down hill, where your mostly having vacuum as engine brake at 140mbar of manifold pressure. and sucking against 0.85 bar is way less energy consuming than compressing to 10.5 bar...

and since i can reset check engine light with my scanner at a buttons touch, i dont care to much that this triggers a fault...

unfortunately the funny contraption of P30 parking brake wont allow me to cut off ignition and then WOT the engine for braking. that would make the auto parking brake apply, ive burned it up once, learned my lesson.
 
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Will L. said:
Vw that I have seen all use hose rated for ethanol .
Trek might have- but GM did not back then
Click to expand...
well i can tell you, the 97 factory GM hoses, they hold up just fine, nice soft, not swollen, looking like brand new. not like the crap that was used by National RV... i don't get how they could accomplish to have such a good name as they had, considering the way they operated.

still have to replace the same National RV extension on the return hose, but that's at least pressure free (mostly)

i still haven't found an adapter from the female side to nylon...

I've found male to nylon, its linked in here further up, but where do you get that darn female fitting?

i want all new hoses made for this. either rubber or nylon, but i need to find the fitting first.

probably have to buy a hose from GM and hope the fitting has a manufacturing marking on it?
 
and once more i was spot on when i walked into 7 garages/shops and asked if they could fix it and that the requited parts are in a fuel line repair kit....

i remember Eric O from the south main auto YouTube channel ranting about exactly this kind of BS once, he was so spot on. thats how i knew that this type of fitting is in this fuel line repair kit. saw it once, years ago, i know about it, folks that work the stuff on a daily basis can't remember it... awesome, isn't it.

so once more those rubbish shop mechanics had no clue about their tools and friggin job....

that picture is from dormans 800-300 nylon repair kit. all parts required right there...

and that from someone who is working on GM the first time in his life versus mechanics doing it all their life.

sorry, I'm kind of worked up about it right now.

how do you guys get anything done over here, dealing with all that widespread stupidity?

i was in all shops and several hydraulic places in a 15km circle in a pretty wealthy and densely populated area. the one place that really put an effort in for helping me, and came the closest in finding the real solution but in the end just sold me the but connectors, hose and clamps, I'm going to teach them my findings....

not the first time i had that happen.

i hate dealing with stupid mechanics and pretty front desk ladies who only are upright cause the vacuum between the ears make em seam to stand on their feet, but in reality they are to stupid or just not interested, to even accomplish that.
 

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mannebk said:
so if i read that right, i can use a SAE 45° flared female to connect to my SAE o-ring short pilot males...

so now i need SAE 45° flared females to nylon fuel hose adapters...
Click to expand...
My son, just today run into this problem with His boat lower unit.
Not sure the size of these O-Ring pilot fittings but they dont fit the new hydraulic unit for the tilt/trim of the drive unit.
IMG_2612.jpeg
 
btw. thats mainly why i fix my own stuff, just imagine you bring your car there and they need to accomplish more than just changing the oil or wheels from summer to winter, and even these 5 year olds tasks these people somehow mange to screw up.
 
MrMarty51 said:
My son, just today run into this problem with His boat lower unit.
Not sure the size of these O-Ring pilot fittings but they dont fit the new hydraulic unit for the tilt/trim of the drive unit.
View attachment 93571
Click to expand...
he needs to get himself an adapter:

SAE female 45° flare to what ever he needs on the hydraulic side.

or cut the short pilot off and use compression fittings out of hydraulics, they seem to be long enough after the 90 elbow for having compression fittings on.

make sure for compression fittings its a steel pipe, not Aluminium... compression doest play well on aluminum, especially with vibrations.... itl shrink, leak and eventually brake.

its not clear on the picture
 
mannebk said:
he needs to get himself an adapter:

SAE female 45° flare to what ever he needs on the hydraulic side.

or cut the short pilot off and use compression fittings out of hydraulics, they seem to be long enough after the 90 elbow for having compression fittings on.

make sure for compression fittings its a steel pipe, not Aluminium... compression doest play well on aluminum, especially with vibrations.... itl shrink, leak and eventually brake.

its not clear on the picture
Click to expand...
I think that in this town, most likely, He will find brass but no steel fittings.
I told Him to take the adapter fittings supplied with the kit out to the local marine shop and see if their lead boat mechanic has run into similar situations and what He did for a fix.
Be tomorrow evening but I will post his findings.
 
if hes cutting, put foam ear plugs into the pipe, then cut and deburr, then peel the left over half earplugs out with a needle or small pliers, that way no chips end in the hydraulic system.

make sure you get all of the plug out...

plenty of dead turbochargers around that did eat some cover rags on first start up. :p
 
the fitting doesn't matter really if its up to the pressure, but the pipe hes putting it on does absolutely matter. never ever put any sort of compression fittings on aluminum....

but for super low pressure system there are aluminum pipes in the market... so he needs to make sure his stuff is actually steel before converting the SAE schort pilot o-ring thingys to compression fittings...

if he uses brass fittings that's fine, as long as they are rated to the pressure the system is rated for.

better to get an adapter...

SAE female 45° flare to what ever he needs on the hydraulic units side.
 
mannebk said:
missing over 30% of your capacity, old fluids and dragging calipers is a real bad combination.
Click to expand...

My mistake. I assumed your equipment, brakes, were 100% although your were saying you were driving a rig having trouble. We have all been there with brake trouble either sudden (like a pad comes off the backing plate) or long term (say obsolete rear drums auto adjusters frozen) creeping up. And trailer brakes always have one random problem or another... With the grades around here I would adjust the rear drums every other oil change.

mannebk said:
what do i need to avoid to not burn up the 3rd overrun clutch?
Click to expand...

You can't as it's simply a weak point in this transmission.

When compression braking in manual 3rd if you ever feel a surging quit using it immediately as it's slipping and burning that small 2 disc clutch over run pack up. Transmission works normally without it: just no compression braking. There isn't much available to make it stronger.

I burnt one with a stock 6.5 diesel feeling the surging. I quit using it immediately and it would still work later.

I burnt another one up faster by forcing the torque converter clutch on, via a switch, while compression braking with a 6.5TD. It lasted 30 seconds and then never worked again. The mod(s) of keeping the TC locked during "lift off throttle" risks snapping the input shaft of the transmission. The ECM is programmed to unlock the TC clutch if you lift off the throttle.

The modification to cut the injectors and open the throttle is a good idea, but, this weak clutch may not be able to handle it.

Perhaps if you are looking at a trans rebuild you might consider a stronger transmission "project" if compression braking is critical.
 
@mannebk
Tell us how you really feel and don’t hold back this time. Haha

Basically it’s a money issue. I was doing amazing work for customers- I would do a rebuild engine and people cried about my price$100 more than “X” down the road throwing in a junkyard engine. Mine would be balanced & blueprinted. Everything set perfectly- and they are worried about $100- seriously multiple times.

Parts- people everywhere get upset about part failures when things used to have a good long life. Then they want to save 5% and buy knock off parts on accident because they won’t buy from legit sources.

I get money is an issue- I’m stuck in that world too. But I don’t cry about it when a cheapskate move costs me more money long term.

So the good parts suppliers switch to cheap. Great mechanics stop teaching their kids to go into the business just like I did. My dad wrenched on and owned world record setting car, before focusing on things that fly. I set a couple records in my day. But there is no way with the horrible pay check that exists now in the field that I would tell anyone to do it for a living. Huge mistake. I won’t do it now- I’m making my retirement money with electricity up to 69,000 volts.
Mechanic income is junk now.
 
@Will L.

haha

you know, i clearly understand it.

but then, do you really need those bitching about 100 bucks?

i fix cars only for who appreciate my work and absolute love to detail. most of my customers are friends or have become friends. they drop of before going on a long distance, i take it around thr block, if they have issues they send me vids. as i keep telling them i don't want description. you dont notice what i notice. your description is worthless for me...
and if someone of my clients brakes down en route, rarely happens besides no fuel or dead tire, i go get them, get their car home to my shop. bring a replacement car.

some have expanded my service to tend to their vacation homes and yachts, since I'm a private pilot even airplanes are in it now.

and it comes back, since years my invoices are paid, no discussion, and i now, after doing that for decades, have access from most of my long term customers to use all their stuff at my discretion like it would be my own, not even footing fuel bills for yacht's and such.

people who start heckling about my rate or that i bill by time spent and don't give quotation. wrong customer. for me quality and reliability comes fist, the customers who value that, they wont discuss pricing with me.

i actually hail from the production equipment maintenance department. i had a customer who, while he had to foot my 10k bills each month, got products out the door sold at millions, then he lost a big customer and his equipment leasing kept coming each month, so after a while he started discussing my bills, i quit after he was in the second sentence. From the last guy to depart the company i heard after i was gone the production went down to almost nothing, nit for having no orders, cause nobody was able to run the equipment. but the owner never called me... rather went out of business.

and on the funny side, my best friend moved his companies fleet to me, took me years to convince him to pay more up front :). but now even with my stuff on top, he's way down in repair and breakdown costs, and the added maintenance costs by my service isn't eating half of it. and not factored in is the time that was wasted by his personnel while stuck with a broken car and missed appointments with customers, bad reputation for being a now show with the customer and such.

he made a nice presentation out of his numbers and gave it to me on my birthday with the hint to rise my rates.... when im back home in Germany i need to fly to sweden and fix up his boat before it gets back into the water for the summer end of May

lucky me, i don't need to earn my income from this, and i only fix myself what i do enjoy, im in for diagnostic, all other stuff, i source out but stand right next to the guy doing it. the few shops i go to use it to educate and train their mechanics, cause i don't hold back if someone does something stupid, but i don't fold em down and take emm off at knee level, ill explain why its a problem and how to do better. as always there are those who appreciate it and learn and those who dont want to work under my supervision. but that's alright , only a few are born to be part of the very best in each profession, and you need all those lots of foot soldiers that do stuff like changing oil and filters.

i don't want to do that on a regular basis, so boring... just imagine changing oil in a lube shop... 15-20 cars per hour 8h each day for 40 years....
 
mannebk said:
thank you so much for you're very detailed explanations

I do not actually do engine braking in third gear if I want to break down I usually force it into second or even first.
Click to expand...

This clutch is only "on" if you select 3, 2, or 1. It's not on in reverse or OD aka 4th. Those who only use "OD" and "R" never use this clutch.

4L80E_overrun.jpg
 
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