cleaning hydraulic lifters
#1
Rennlist Member
Thread Starter
cleaning hydraulic lifters
Has anybody ever disassenbled and cleaned the hydraulic lifters? Here is a video that shows how to do it for VW 16V lifters.
#3
Rennlist Member
Thread Starter
After careful inspection, it appears that the hydraulic lifters of the early 928 are quite different from the VW lifters that are shown in the "cleaning hydraulic lifters" youtube movie I posted above.
The construction of the hydraulic lifters of the 944 and (early) 928 are clearly shown in another youtube movie, where a hydraulic lifter is cut in half to show its internals.
This movie proves that the hydraulic lifters of the early 928 cannot be disassembled to clean out. The plate that is pressed in has a rubber seal underneath it that is probably not renewable. And the plate cannot be removed from the lifter.
As my lifters are totally stuck because they were taken from the engine a long time ago, something had to be done. So I tried some treatments to free up the piston.
First I put the lifter in a bath of engine cleaner to soak. After a couple of days I rinsed it to remove the gunk. Second, I pressed the piston in with a vice and a smooth piece of metal(to point at the piston) and some cloth to protect both sides of the lifter. It took some force but eventually it gave way.
Third, I gave it a hot bath with a caustic cleaner to really clean it, frequently puching the piston to let the detergent in.
After letting it sit for a couple of hours, I rinsed the lifter again and removed the water by spraying it outside and into the hole with WD 40. The lifter looked like new now and worked really smoothly.
The last step I want to do is to put the lifter in an oil bath of synthetic engine oil and heat it to 120 degr C to remove the residual water, frequently pushing the piston.
I am pretty confident that this procedure will clean the lifter on the inside as well as the outside. What do you think of this procedure?
The construction of the hydraulic lifters of the 944 and (early) 928 are clearly shown in another youtube movie, where a hydraulic lifter is cut in half to show its internals.
This movie proves that the hydraulic lifters of the early 928 cannot be disassembled to clean out. The plate that is pressed in has a rubber seal underneath it that is probably not renewable. And the plate cannot be removed from the lifter.
As my lifters are totally stuck because they were taken from the engine a long time ago, something had to be done. So I tried some treatments to free up the piston.
First I put the lifter in a bath of engine cleaner to soak. After a couple of days I rinsed it to remove the gunk. Second, I pressed the piston in with a vice and a smooth piece of metal(to point at the piston) and some cloth to protect both sides of the lifter. It took some force but eventually it gave way.
Third, I gave it a hot bath with a caustic cleaner to really clean it, frequently puching the piston to let the detergent in.
After letting it sit for a couple of hours, I rinsed the lifter again and removed the water by spraying it outside and into the hole with WD 40. The lifter looked like new now and worked really smoothly.
The last step I want to do is to put the lifter in an oil bath of synthetic engine oil and heat it to 120 degr C to remove the residual water, frequently pushing the piston.
I am pretty confident that this procedure will clean the lifter on the inside as well as the outside. What do you think of this procedure?
#4
Rennlist Member
Thread Starter
Not many people have responded to my suggested cleaning procedure of the hydraulic lifters. I think because for most people this may not be an issue.
My engine has been sitting for some years now and alle lifters are totally stuck. I tried some methods of getting them going again and I think I have the total cleaning procedure figured out now. This is a multi stage cleaning process.
1. soak in engine cleaner for some days. inject engine cleaner into the lifter with a syringe through the hole
2. rinse with hot water, also inject into the hole
3. dip in hot caustic cleaner solution and leave it there for some days. Also inject the caustic solution with the syringe into the hole to get rid of the water/engine cleaner
4. rinse with RO water, also flush with syringe in the hole to remove the caustic cleander solution
5. rinse with alcohol 96% to remove the water. Also inject with syringen into the hole
6. let it dry, perhaps use some heat
7. soak lifter in engine oil and heat the oil to 250 F and also inject engine oil into the hole
It may seem very laborious but this seems to remove the muck and replace it with new engine oil. That sounds like music to me!
But to be sure it is effective I would like to clean an old lifter that is totally stuck using this method and dismantle it (this will destroy the lifter) to see if the inside valves and plungers are indeed cleaned and lubricated properly.
IMPORTANT QUESTION
Who is willing to send me one or more lifters (dirty and stuck) to experiment? These will not be returned. I will pay for the freight. These lifters need to be of the early type that cannot be taken apart
My engine has been sitting for some years now and alle lifters are totally stuck. I tried some methods of getting them going again and I think I have the total cleaning procedure figured out now. This is a multi stage cleaning process.
1. soak in engine cleaner for some days. inject engine cleaner into the lifter with a syringe through the hole
2. rinse with hot water, also inject into the hole
3. dip in hot caustic cleaner solution and leave it there for some days. Also inject the caustic solution with the syringe into the hole to get rid of the water/engine cleaner
4. rinse with RO water, also flush with syringe in the hole to remove the caustic cleander solution
5. rinse with alcohol 96% to remove the water. Also inject with syringen into the hole
6. let it dry, perhaps use some heat
7. soak lifter in engine oil and heat the oil to 250 F and also inject engine oil into the hole
It may seem very laborious but this seems to remove the muck and replace it with new engine oil. That sounds like music to me!
But to be sure it is effective I would like to clean an old lifter that is totally stuck using this method and dismantle it (this will destroy the lifter) to see if the inside valves and plungers are indeed cleaned and lubricated properly.
IMPORTANT QUESTION
Who is willing to send me one or more lifters (dirty and stuck) to experiment? These will not be returned. I will pay for the freight. These lifters need to be of the early type that cannot be taken apart
#5
Nordschleife Master
I'd be concerned that the lifters remain contaminated with solvent or that it'll jam up, again, in operation. A quick check shows that new lifters are over $200/ea! I'm softening on this but 928I offers used ones for $15/ea. I'd greatly prefer, for my builds, to work with unstuck lifters. Maybe use some light penetrating oil to clean them.
#7
Archive Gatekeeper
Rennlist Member
Rennlist Member
Blow out the plunger with compressed air (via the drain hole), and put 'em in an ultrasonic cleaner with some detergent to agitate them. There will be a satisfying cloud of crap and sludge that will be liberated from the built-in 'shelf'.
Good thread on lifters, with cleaning advice starting in post # 53:
https://rennlist.com/forums/928-foru...h-87-s4-2.html
Good thread on lifters, with cleaning advice starting in post # 53:
https://rennlist.com/forums/928-foru...h-87-s4-2.html
Trending Topics
#8
Rennlist Member
Thread Starter
Blow out the plunger with compressed air (via the drain hole), and put 'em in an ultrasonic cleaner with some detergent to agitate them. There will be a satisfying cloud of crap and sludge that will be liberated from the built-in 'shelf'.
Good thread on lifters, with cleaning advice starting in post # 53:
https://rennlist.com/forums/928-foru...h-87-s4-2.html
Good thread on lifters, with cleaning advice starting in post # 53:
https://rennlist.com/forums/928-foru...h-87-s4-2.html
The old style lifters cannot be disassembled. As you can see from thesecond movieI posted, "What's inside a hydraulic lifter", the plunger is held in place by the top deck that is pressed in place.
I like the ultrasonic cleaner suggestion. I am going to try that with detergent.
#9
Former Vendor
If you study that cross sectional picture of this style hydraulic lifter and think about how it is oriented in the engine, you can see that the "U" shaped area can and does get filled with "crud".
This "crud" is usually a very hard packed, multiple layered sludge....impossible to remove without some very "aggressive" work. If you've ever seen a "sludge trap" inside a motorcycle crankshaft, this is exactly what happens in this style lifter.
Porsche instructed that the lifters get thrown away, in any engine failure, because of this. Chunks of metal from the failure can (and will) "pack" into this area....breaking loose after rebuilding, ruining the "new" engine.
I've cut open many lifters, to study this. The amount of "sludge" that collects in this area, just in higher mileage engine, is mind boggling. A layer of thick sludge can form all the way to the top edge of the "plunger" hole. If there has been coolant in the engine....it's even worse. Late model engine with thrust bearing failure are absolutely packed with crap.
A bucket" of used lifters looks like a mountain of engine failures, to me....make sure you know the history of the used lifters you are considering to use them!
And cleaning any lifter from the outside to get rid of the layers of sludge inside seems impossible to me.
32 valve lifters can be taken apart and various tools can be used to scrape out and rinse out the "crud". It sometimes takes major effort and many scrapings and many washings to get them clean. New lifters start to look like a bargain, by the time you are done.
I've never figured out how to get a 16 valve lifter apart to clean them. If anyone that has figured this out, I'd be thrilled to hear how.
When I used to build large quantities of 951 engines, I tossed hundreds of these lifters in the trash, due to bearing failures....some on engines which had been just "rebuilt" (by others) and ruined the "new engine" immediately.
This "crud" is usually a very hard packed, multiple layered sludge....impossible to remove without some very "aggressive" work. If you've ever seen a "sludge trap" inside a motorcycle crankshaft, this is exactly what happens in this style lifter.
Porsche instructed that the lifters get thrown away, in any engine failure, because of this. Chunks of metal from the failure can (and will) "pack" into this area....breaking loose after rebuilding, ruining the "new" engine.
I've cut open many lifters, to study this. The amount of "sludge" that collects in this area, just in higher mileage engine, is mind boggling. A layer of thick sludge can form all the way to the top edge of the "plunger" hole. If there has been coolant in the engine....it's even worse. Late model engine with thrust bearing failure are absolutely packed with crap.
A bucket" of used lifters looks like a mountain of engine failures, to me....make sure you know the history of the used lifters you are considering to use them!
And cleaning any lifter from the outside to get rid of the layers of sludge inside seems impossible to me.
32 valve lifters can be taken apart and various tools can be used to scrape out and rinse out the "crud". It sometimes takes major effort and many scrapings and many washings to get them clean. New lifters start to look like a bargain, by the time you are done.
I've never figured out how to get a 16 valve lifter apart to clean them. If anyone that has figured this out, I'd be thrilled to hear how.
When I used to build large quantities of 951 engines, I tossed hundreds of these lifters in the trash, due to bearing failures....some on engines which had been just "rebuilt" (by others) and ruined the "new engine" immediately.
#11
Former Vendor
The lifters from the early years are different from thos in a 944 or an S4. The first movie I posted is about 944 or VW lifters.
The old style lifters cannot be disassembled. As you can see from thesecond movieI posted, "What's inside a hydraulic lifter", the plunger is held in place by the top deck that is pressed in place.
I like the ultrasonic cleaner suggestion. I am going to try that with detergent.
The old style lifters cannot be disassembled. As you can see from thesecond movieI posted, "What's inside a hydraulic lifter", the plunger is held in place by the top deck that is pressed in place.
I like the ultrasonic cleaner suggestion. I am going to try that with detergent.
And in the last few minutes of an engine failure, when the oil filter gets plugged and bypasses, the a mount of crud circulating around in the oil system is horrific.
If you ever get to remove the oil pan from a late model 928 engine that has experienced thrust bearing failure, that 1/4" thick layer of "engine clay" is exactly what is inside the lifters.