Coolant in VOD

[DavidProehl]

I have coolant leaking into my VOD, so I spent some time today getting down to it. I'm pretty sure my leak is coming from a poorly clamped water pump hose, but wanted to run this by the crew here to get a gut check. I replaced all the rubber hoses and did a cleaning in 2011, so I'm wondering if I need to pull the water pump and replace these hoses again or if I could get by tightening up the hose clamps?

My assumption is that I'm about to be told not to be lazy and just replace the hoses...I'm just really not looking forward to pulling the water pump to replace newish hoses.


Where it looks like the main leak is:
43511


A pool of coolant I need to clean up:
43510

[burch]

I had the same issue last year, and know that the PO replaced the hoses with quality replacements a couple of years ago. I just tightened everything down, pressure tested the crap out of it multiple times, and put KJet back together. No issues as of yet, but I can understand changing everything out while you are in there.

[sdg3205]

re-tighten and pressure test. It should hold 15 PSI for a good while. No need to throw new hoses at it.

[DavidProehl]

Great idea! Not sure why I didn't think to pressure test. I'll start by going that route. Thanks!

[David T]

The hoses and clamps have been changed, they are not original. Make sure the "O" ring seals are not leaking at the connections of the "Y" pipe to the block. I have found just tightening is not always the best way to go because when the coolant leaks it causes deposits to form making it difficult to get a good seal. The joint should be taken apart, cleaned, and reassembled with sealer. Just tightening the clamp risks overtighening the clamp to stop the leak and breaking the clamp. PJ Grady sells silicone hoses and clamps for those hoses so they will never require additional tighening to stop future leaks. Just what is needed there as it is a LOT of work to get to those clamps!

[dn010]

You can get away with replacing those hoses coming off the sides of the pump without actually having to remove the pump. You just have to bend the hoses correctly to get them on and use silicone spray to help.

[DavidProehl]

The hoses and clamps have been changed, they are not original. Make sure the "O" ring seals are not leaking at the connections of the "Y" pipe to the block. I have found just tightening is not always the best way to go because when the coolant leaks it causes deposits to form making it difficult to get a good seal. The joint should be taken apart, cleaned, and reassembled with sealer. Just tightening the clamp risks overtighening the clamp to stop the leak and breaking the clamp. PJ Grady sells silicone hoses and clamps for those hoses so they will never require additional tighening to stop future leaks. Just what is needed there as it is a LOT of work to get to those clamps!

I appreciate the tips! I'll take a look at the silicone hoses.


You can get away with replacing those hoses coming off the sides of the pump without actually having to remove the pump. You just have to bend the hoses correctly to get them on and use silicone spray to help.

That sounds like a great compromise...if I'm able to get them back on. Worth a try.

[David T]

I appreciate the tips! I'll take a look at the silicone hoses.



That sounds like a great compromise...if I'm able to get them back on. Worth a try.

You should not use silicon lube. It can make the hoses easier to slip off. Lubricate with anti-freeze.

[DavidProehl]

I re-seated the hoses, and put the loaner AutoZone pressure tester on it. While my freshly tightened hoses held like champs, there were 3 other areas on the car where coolant started dripping out. Now everything is tightened up, and seemingly no leaks. I'm letting it sit overnight at 15 psi. I never noticed any leaks like I was seeing, so the car must operate far below 15 psi, but it is good to have these fixed.

I feel a little foolish for never putting a pressure tester on the car before now. I'm officially a pressure test evangelist. This really is a must any time you open up the coolant system.

[sdg3205]

I re-seated the hoses, and put the loaner AutoZone pressure tester on it. While my freshly tightened hoses held like champs, there were 3 other areas on the car where coolant started dripping out. Now everything is tightened up, and seemingly no leaks. I'm letting it sit overnight at 15 psi. I never noticed any leaks like I was seeing, so the car must operate far below 15 psi, but it is good to have these fixed.

I feel a little foolish for never putting a pressure tester on the car before now. I'm officially a pressure test evangelist. This really is a must any time you open up the coolant system.

They are invaluable tools. It travels with me in the delorean the same way my OBDII scanner lives in my Jeep!

[Rich]

....I'm officially a pressure test evangelist. This really is a must any time you open up the coolant system.

Good call, David! Couldn't agree more.

Glad you got some peace of mind from the test and the fix now that the summer driving season is there.

Note to all owners, as a bonus a good pressure test kit also includes a rad cap test adapter. Knowing that the radiator (or coolant header tank) cap can hold 15PSI is also a must - the cap gaskets/seals don't last forever.

[bfloyd]

I still have my "loaner" pressure tester from Autozone from when I rebuilt the car last summer. The deposit I paid is essentially the purchase price.

[DavidProehl]

Good call, David! Couldn't agree more.

Glad you got some peace of mind from the test and the fix now that the summer driving season is there.

Note to all owners, as a bonus a good pressure test kit also includes a rad cap test adapter. Knowing that the radiator (or coolant header tank) cap can hold 15PSI is also a must - the cap gaskets/seals don't last forever.

Ah, I saw the two sided adapter, that is what it is for! Makes sense.

It was great seeing you in the Eurofest video! Looked like an amazing time. Maybe I'll get there in 5 years....

[David T]

Pressure testing is a very good test but after repeated heat-cool cycles the hoses "creep" and the clamps loosen and must be retightened unless you used silicone hoses. The hoses under the intake manifold can't easily be retightened, that's why it's worth the extra cost to use the silicon hoses.

[PJ Grady Inc.]

Pressure testing is a very good test but after repeated heat-cool cycles the hoses "creep" and the clamps loosen and must be retightened unless you used silicone hoses. The hoses under the intake manifold can't easily be retightened, that's why it's worth the extra cost to use the silicon hoses.

We've been using only silicone hoses and non-slotted clamps at the rear of the pump since the mid-eighties because they don't pack down or need re-tightening over time like normal rubber hoses do. This is where a small investment in a quality hose and clamp combo will pay big dividends. Conventional hoses will usually pack down and leak after a few years. Personally I would always opt for silicone in this application but you can probably get away with re-tightening them every few years if you enjoy pulling the intake manifold to do so!
Rob

[kings1527]

I re-seated the hoses, and put the loaner AutoZone pressure tester on it. While my freshly tightened hoses held like champs, there were 3 other areas on the car where coolant started dripping out. Now everything is tightened up, and seemingly no leaks. I'm letting it sit overnight at 15 psi. I never noticed any leaks like I was seeing, so the car must operate far below 15 psi, but it is good to have these fixed.

I feel a little foolish for never putting a pressure tester on the car before now. I'm officially a pressure test evangelist. This really is a must any time you open up the coolant system.

That might be one of those things to just go ahead and purchase to have at home. I picked up a great, used Snap On pressure tester of eBay for much cheaper than you'd think (maybe $100 or so) and it's hard to believe how often you break it out. Kind of like when you first get an air compressor. It's just so convenient when you want to rule out a leak or if you have a leak going and want to pinpoint real quickly where it's coming from. A real key piece of equipment.

[DavidProehl]

I was losing about 1.5 psi in a 24 hour period so I decided to pull the y pipe even though the seals were less than 5 years old. Looks like one of them went bad:
43579

Pressure testing again tonight. If all is well tomorrow I can finally reassemble!

[kings1527]

I was losing about 1.5 psi in a 24 hour period so I decided to pull the y pipe even though the seals were less than 5 years old. Looks like one of them went bad:
43579

Pressure testing again tonight. If all is well tomorrow I can finally reassemble!

That seal obviously doesn't look good but losing 1.5 psi/24 hours isn't bad at all. Usually you'll see something come up with a couple minutes. And it's different pressure testing with a cold system. When things heat up, the hoses will swell just a bit and close off anything that isn't 100% tight.

[sdg3205]

I think i heard 15 psi for 30 minutes is a good indication of system pressure health.

[fnzen]

from the pics it looks like you are running pure antifreeze you may want to "water down" the % too

definitely recommend that you take them off now that you are in there as there is alot of deposits around the edges and thats not right

[DavidProehl]

from the pics it looks like you are running pure antifreeze you may want to "water down" the % too

I'm running a 50/50 mix. I'm guessing the reason it looks so pure is because the water boils off an leaves the anti-freeze behind.

[novadmc]

We've been using only silicone hoses and non-slotted clamps at the rear of the pump since the mid-eighties because they don't pack down or need re-tightening over time like normal rubber hoses do. This is where a small investment in a quality hose and clamp combo will pay big dividends. Conventional hoses will usually pack down and leak after a few years. Personally I would always opt for silicone in this application but you can probably get away with re-tightening them every few years if you enjoy pulling the intake manifold to do so!
Rob

this is my issue currently. put on a fresh rubber hose supplied by DMCH from the pump to y-pipe last year. and now its starting to leak. ripping the intake off sometime this weekend or next week to take a look. hopefully the hose just needs adjustment/clamp tightening.

IF that hose needs replacement or if i decide to replace it, is it possible to replace that big pump to y-pipe hose (with a new silicone hose) without having to remove the y-pipe or pump? since i've got no other leaks (heater core, y-pipe o rings, etc) i'd rather not risk disturbing any other lines if i don't need to.

[Morpheus]

You will need to remove at least one or the other, and possibly both depending on if it goes smoothly or not. Removing the Y-pipe can be a harrowing experience if you break off a bolt, so if it were me I would remove the WP and swap it out that way.

Another thing to keep in mind is this: a bolt can break off anywhere, but seems to happen most often when dealing with the cooling or exhaust system.

[cpistocco]

Does anyone know if it is possible to change the hoses around the water pump without removing the intake? It looks like a real PIA!
Thanks
Charlie

[Morpheus]

I don't think that's possible. Removing the intake isn't all that difficult, but it's something people hate doing because of the effort involved in putting everything back together correctly without vacuum leaks. That said, once you have taken it off once, you can do it the next time pretty quickly.

Besides, how else are you going to clean out the valley with the intake in the way?

[louielouie2000]

I don't think that's possible. Removing the intake isn't all that difficult, but it's not something people enjoy doing because of the effort involved in putting everything back together correctly without vacuum leaks.

Besides, how else are you going to clean out the valley with the intake in the way?

The previous owner of my second DeLorean took the car to a Volvo shop to have the water pump replaced, and he claims they did it without removing the intake. I suppose with the right tools, lighting, and hose clamp alignment it must have been possible.

To me, water pump replacement on a DeLorean is the best excuse to do deferred maintenance like replacing your spark plugs, spark plug wires, cap & rotor, coolant hoses, vacuum lines, vacuum components, intake O-rings, clutch hydraulics, check for block rot, etc.

[sdg3205]

To me, water pump replacement on a DeLorean is the best excuse to do deferred maintenance like replacing your spark plugs, spark plug wires, cap & rotor, coolant hoses, vacuum lines, vacuum components, intake O-rings, clutch hydraulics, check for block rot, etc.

+1

Give the VOD a good clean, scoop out the crud and rinse out those deep pits.

[burch]

Might pick up one of these ShopVac micro accessory kits for the next time I'm in there. Be real easy to go in and suck out any crud in the nooks and crannies (being careful not to suck up anything else): https://www.amazon.com/Shop-Vac-Micro-cleaning-80189-1-1/dp/B00002ND4G

[David T]

Just duct tape a short piece of small diameter hose to a wet/dry shop vac. Finish up with some paper towels. Might need to loosen the debris up with a small, thin screwdriver.

[DMCVegas]

Does anyone know if it is possible to change the hoses around the water pump without removing the intake? It looks like a real PIA!
Thanks
Charlie

If you're talking about the two Upper Hoses on the sides of the Water Pump which connect to the flanges on the Cylinder Heads, yes, it *is* possible to replace those hoses without pulling the intake manifold. I've done it. I had to remove the inlet and outlet hoses from the Water Pump, the W-Pipe from the intake manifold, and disconnected the throttle assembly and linkage from the valves.

I will warn you though, THAT was the most difficult repair I've ever done on the car, because by not pulling the manifold and pump off I made it insanely more complex than it needed to be. You have to trim the hoses a bit, and then fold them into place, and stretch the openings out in order to get them to go around the connecting plumbing.

I actually spent more time fighting those damn hoses than I actually did pulling and reinstalling the manifold later when I decided to bite the bullet and replace the pump which did require removal of the manifold. At that time the new hoses just slipped right on as I lowered the pump into place and didn't give me any trouble at all. So take it from me: Pull the manifold and just replace everything.

Water Pump replacement has always been every DeLorean owner's Right of Passage. Not because it is difficult, but because it seems difficult and requires you to overcome allot of fear and build up the courage to do it. But once you do, there won't be much else on this car you won't be able to tackle.

[novadmc]

Water Pump replacement has always been every DeLorean owner's Right of Passage. Not because it is difficult, but because it seems difficult and requires you to overcome allot of fear and build up the courage to do it. But once you do, there won't be much else on this car you won't be able to tackle.

so much this ^^^

i had to replace the pump just over a year into ownership (it was leaking when i got it, but i figured screw it, ill drive it till it gets bad).
the entire time i was disassembling the intake and exposing the valley i was worried of getting in over my head. tho to be honest, reinstallation probably had me more worried because i was so worried about leaks (fuel or coolant) or that i'd screw something up and ruin the car.

this past May i had to go back into the valley to fix that coolant leak from the hose clamp and rather than be pensive/afraid of doing it again, it was just annoyance. not even any frustration.

it was also a lot quicker 2nd time around! 1st time took probably ~2-3hrs to disassemble, note where everything went, etc. reassembly probably took the same amount of time. 2nd time took about 90mins to rip everything out. I got 95% of it back together (minus bolting down the fuel lines) in 60 mins.

[David T]

As bad a job as it may be, it is made much worse if you break any bolts. Once you have done the job it is not as likely for any bolts to break anymore. Not every owner will do this job, many are "Mechanically Challenged" and prefer to pay others to have the fun. For all of the trouble you will have doing the pump without removing the intake manifold, it is just as much work (probably less) to take the intake manifold off. Consider it a once-every-20-year job. Gives you the opportunity to do a full tune-up too. BTW, just how do you get to the hoses on the back of the water pump without removing the intake manifold?

[cpistocco]

Thanks Guys....You are great! With that said, I feel like my D is becoming a part time job....I swear that I have replaced everything that you can replace on the car ! So I am not sure that I need any more "rites of passage". I am starting to get that lazy feeling ! If I can avoid pulling the intake, then I will... :) ( I will get to the VOD sooner or later)

[cpistocco]

By the way..... I just wanted to say that you guys are a "hearty" bunch. As Delorean owners you have to be witty, crafty, cooperative, patient, smart, handy, and forgiving.... I have owned many classic cars- Mostly GM's....and a 40 year old car might require an occasional oil change.....calipers, master cylinder, or radiator.....and that is it! It is a breeze next to a D ! I never had to pull an intake to tune up my 74 vette! :) There is a place for all of you in Heaven!