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21 Turbo G788 WUD

Yeah, I fitted all new belts when I did the timing belt and tensioner. The old water pump/alternator belt was worn down to about 6mm wide, so it was long overdue.
Like you say, now it's got belts on there and they are tensioned up, it's just the final straw for the water pump. Strangely, when I ran the engine a few weeks back, when I discovered that the exhaust was knackered, the water pump seemed OK. Now, it's like a Catherine wheel of anti-freeze emerging from the water pump pulley.

Never mind. New water pump ordered, and i'll give it a go next weekend if it arrives in time.

So, judging by your photos, it's two studs and four bolts holding it?

I'll get some bolts on order too!

Cheers
 
Yes, I replaced mine with all bolts though, just be careful it positions right and the gasket is in the right place. Dont overtighten as the ally threads will strip.

There six bolts for the pump and two for the housing for the bottom hose (which may well snap too), so eight all told.
 
So replacing the waterpump was my punishment for today. I did make a start yesterday, by removing the nosecone, intercooler, radiator etc, and the PS and Alternator belts.
Like Dave predicted, removal of the pump was a PITA. Two bolts did remove cleanly, one of which was from the bottom hose housing. The nuts from the studs came off fine too. So, four broken bolts to deal with. Luckilly, they broke just below the heads, so left me with plenty of meat to play with.
I gave the pump a beating with a hammer to try to knock the corrosion loose, and I could feel that it was no longer tight against the block, but I just could not get it to budge.
To make life a bit easier, I managed to unscrew one of the studs by double nutting it. The other broke off, again with plenty of meat left.
Now, my technique, instead of breaking the pump up with a cold chisel, was to use a 19mm holesaw, with the pilot bit removed, to cut around the mounting bosses as deep as the sandwiched steel plate. This allowed me to wiggle the now cut through bosses one at a time with a set of grips until they were free. The pump then came off fairly complete.

I then had all of the broken studs/bolts to deal with. Two came out with just using grips on the shanks, one came out after i'd broken it about 6mm away from the block by welding a nut to it, and the others I ended up drilling and cleaning out the threads with an M7 tap.

I bought a pack of M7x45 bolts to mount the new pump. Realising though that the two studs i'd removed were actually screwed into holes entering the water circuit, and that 45mm bolts were too long for these two positions, I lopped the heads off two of them, and set them in place of the studs with liquid PTFE. I was going to use threadlock, but at least with liquid PTFE, the studs will remain removable without too much faff if needed. I had a load of M7 nuts spare from when I refurbed my OZ split rims, so used a couple of those on the studs.

Sorry I don't have any photos of the actual process, I just wanted to get the job done. Have some after photos though. Still got to put it all back together though, but that's fairly straightforward.
20161008_160309.webp 20161008_160329.webp 20161008_160336.webp
 
Right, well I haven't had much time recently to do much to the car, until today.

Job for today was to get the clutch and front brakes bled, so I can move the car under it's own power, so I'm able to turn it around and be nose into the garage rather than the boot, so I can work on the rear brakes more easily.

Anyway, after reading many clutch bleeding threads, and all of the woes, I thought how hard can it be? Well, the clutch does work and disengage, but right at the bottom of the pedal travel. Plus, the pedal only comes back half way unless it's pulled back by hand, the it gets held by the little spring shock absorber thing. I took the split pin out at the pedal end, and the push rod almost doesn't seem long enough, or the piston isn't returning all of the way back.
The clevis on the end of the pushrod is pretty well ovaled and isn't a good fit on the pedal pin anymore, but it's not causing that much play.
Could I still have air in the system? or a problem with the piston in the master sticking? I rebuilt the slave already, and i'm pretty confident that it's not the problem.

I'm guessing that I have an early phase 2 system. Bleed nipple next to the slave, and one on the master attached to a little rubber tube. Bled the master first, then the slave.

Oh, and my Scorpion exhaust finally arrived. Looks a little butchered, some of the mountings have been chopped off, and the rear box hanger has been replaced by a ducting hanger. The middle box also needs chopping out and replacing, but overall, i'm happy with it. Oh, and the downpipe is most definitely stainless, and it even has a lambda boss installed already.

20161028_132537.webp
 
Are you getting a fluid flow through to the clutch slave? You need to make sure the master cylinder fully returns, so dont pull the pedal up by hand - you need to make it return itself to prove the master piston is returning fully (the rod from the pedal does not attach to the master piston, so pulling the pedal up by hand will not do this).
Pump the pedal a few times and let it sit where it returns to. Jam a big flat blade screwdriver (or similar) down the back of the clutch fork so you can lever it toward the engine. Use this to push the slave piston in, the fluid being pushed back up the circuit should push the master piston back up to the point it vents to the reservoir, you may well hear the pedal 'thunk' as it returns to the home position.
Now pressure bleed it with an eezibleed and about 20psi. Pressurise the reservoir after filling it with loads of fluid, open the nipple and let fluid flow through top to bottom. Make sure the fluid doesnt drop so low as to let air blow through the master or you'll have to start over...I usually tilt the car to aid this (raise pax side).
Close the nipple before depressurising the master.
Give it few pumps and see how it is.

I swear by pressure bleeding for these systems, never do it the normal way.

The wear on the pedal rod is normal. Not ideal, but normal. You can fix it if you can be arsed, the clutch master needs to come out and thats a pain of a job. You have to unbolt the brake master and move it forward but theres enough give to do that without disconnecting brake lines fortunately.
 
Hi Dave,

So, I pried back the clutch slave as you suggested, and with a lot of effort, it clunked and the pedal was at the top. Proceeded to bleed with the pressure bleeder, and more air came out. Flushed about another 200ml through for good measure.
Pressed the pedal, and on return, it's stuck halfway again. Great.
Pried back the slave again, and tried again, but same result.

I noticed that the slave pushrod seemed a long way out (perhaps the fork pivot is worn out?), so shimmed the slave out about 7mm (5 M8 washers on each ear), bled it all again for good measure, but same result, although it seems easier to pry back. I peered down a hole in the top of the bell housing, and can see that the clutch has meat on, so it's not that causing the excessive extension of the rod.

So, whats left, clutch master sticking half way? Is it worth putting new seals in these, or replacing (if I can find a good one)?
 
On the clutch fork i'm getting around 9-10mm so a little less than what the book says. That is measured using a tape measure balanced on top of the slave, and a mobile phone recording balancing on the coil, so can't be 100% sure.

I'm pretty sure that the master is knackered... isn't it meant to have a spring inside that returns the piston all the way out? Well mine either must be broken or the seal is swollen and catching something internally, because it still doesn't fully return back unless I go back to the clutch fork and pry it back.

Anyway.. a little research shows me that a Renault Trafic clutch master cylinder is pretty similar so I may take the plunge and order one up.

The hole spacing is the same on the mounting, piston diameter is right and the hose connection is the right thread. It just looks a little shorter in length.

Amazon product ASIN B00BU77URI
A bit more research shows that the Delorean slave is the same as is used in other Renaults too, Master, Trafic, Espace, R20, R25, R30, just would have to relocate the bleed nipple.

Amazon product ASIN B00CPO2ALQ
 
A bit more research shows that the Delorean slave is the same as is used in other Renaults too, Master, Trafic, Espace, R20, R25, R30, just would have to relocate the bleed nipple.
It is indeed (uses a Renault UN series box)

There is a spring inside the master, but theyre a bit crap. Did you have any issues with the clutch system being seized before all this started?
 
I didn't have any issues with it being seized, but I was aware of a clutch hydraulic problem when I bought the car. The previous owner reckoned it just needed bleeding.

Before I resealed the slave cylinder, the clutch was doing pretty much the same as it is now, but the rest point of the pedal was even lower to the floor.

If i'm allowed by SWMBO over the weekend, i'll take out the master cylinder and have a look, and perhaps even try out the trafic cylinder if it arrives in time.
 
The return action is driven by the clutch spring pushing the slave back and thus the master, if you get full travel/pedal sweep down, you should get it back up again unless there is air in there thats compressing, or something else is wrong (like the master has a bore thats too big, or the fork is shagged on the pivot or something).

If you pump the pedal 15 or 20 times does it improve at all on the return?
 
Right, I ventured out into the cold, dark garage to have another little play tonight, whilst the wife and child are away for the evening. My aim was to try to rule out the fork/pivot being knackered, causing my lack of return at the pedal. What I did was to get my bestest little pry bar and try to gently pry back the clutch fork as I opened up the slave bleed nipple. The fork and slave moved right back without much effort. This is in contrast to when the system is closed, I have to heave on the pry bar to get the pedal to pop back up. When it does pop back up, it does it all of a sudden like something is giving way.
There has got to be a problem internally to the master to be causing this. If I was feeling more motivated, i'd have stayed out and removed it, but it's been a long day at work and the chair is too inviting.
I'm quite sure there was no air in the system after pressure bleeding it and flushing so much fluid through. There were no air bubbles coming through my clear pipe into my jam jar, and when exercising the system with the pry bar behind the fork, I could see no air bubbles rushing back and forth in the nylon clutch pipe.
Pumping the pedal numerous times created no improvement, although it did when the car was first delivered to me, before I started pulling it apart. Even then, the pedal was even lower than it is now.
ETA on the Trafic master cylinder is tomorrow or Friday. Hopefully it'll go in without too much messing, but everything on this car so far has been ball ache! lol. I do like to pick these unloved oddball cars.
 
When it does pop back up, it does it all of a sudden like something is giving way.
Thats the spring capsule on the pedal. There is an assister spring that makes the lower pedal travel lighter (by 17% apparently!), about halfway up the pedal return it goes over its pivot point and pushes the pedal up rather than down.
It sounds like the master isnt returning the piston properly unless you force it up with the slave then. I wonder if there is damage to the inside of the cylinder or something. Is there any fluid leaking out of the master down the back of the bulkhead, in the footwell?
 
Long time no update.

Well, the clutch is all sorted. The original master cylinder had a ring of corrosion on the cylinder, stopping the piston from returning home. I already had the Trafic master cylinder, so instead of ordering a repair kit for the original, I just fitted the new unit instead. It goes straight in, although I had to use M7 nuts and bolts to hold it in place, which was a bit of a pain on my own. The push rod also needed shortening by about a quarter of an inch. The orientation of the feed and pressure lines were slightly different, but it all works ok.

Now, onto the brakes.... namely the rears. Am I right in saying that if I try to bleed them in a conventional manner (with an empty accumulator) I won't get any fluid flow when pumping the pedal? If the accumulator is full, will fluid spray out upon opening the nipples?

Only asking because I've been replacing the rear pipes, cleaning and freeing up the calipers, fitted new pads and hoses, and I was struggling to bleed it today (without realising I needed to do it a special way). I though that here we go, a knackered master cylinder now!

I did have a line cracked open under the car and the ignition on at one point, but no fluid came streaming out. I suppose I need to start checking the pump? I did replace the pipe leading to the accumulator a while ago, and it was definitely pressurised then. Lots of foamy brake fluid came out.
Also, I can't say that i've seen the ABS light come on with the ignition, is it meant to?
Hopefully it's just a fuse or bad wire, but knowing this car, it's probably more.
 
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