Need help with source of major oil leak

[baseball_fan]

My Delorean developed a sudden, major oil leak. A quart leaks out in about 30-60 seconds when the engine is running. It seams to be coming behind the timing gear cover and gasket, behind the water pump, directly below the intake manifold. It looks to be slightly to the left of dead center of the engine when facing the rear of the car. When the oil is leaking it is making a gurgling sound. I removed the two pulleys to see better. I have attached a picture. Any ideas of what could be wrong or how to troubleshoot this problem would be greatly appreciated.

[baseball_fan]

Naturally my photo somehow rotated itself, it's should be reversed-can't figure out to fix the uploaded picture

[DMC-81]

Wow, that is a major leak. My suggestion is to clean the area well, and then have someone start the engine while you look at the area with a good flashlight. This helps pinpoint the exact area, as oil can travel from the source and fool you. From the description of the volume of oil, it seems that something near an oil gallery is leaking (leading from the oil pump, either at a gasket, or through a compromise in the metal.

[Ron]

Naturally my photo somehow rotated itself, it's should be reversed-can't figure out to fix the uploaded picture
Check out this thread...

http://dmctalk.org/showthread.php?15626-How-to-rotate-uploaded-pictures

Have a pic from further back?

[David T]

Sounds like a bad case of "Block Rot". Pull the intake manifold and examine the top of the block. No easy fix.

[Josh]

My car had block rot. I never had the car running with the stock engine, but just turning it over by hand made oil "waterfall" over the timing cover like you see.
The oil comes from one or more of the 4 deep pockets in the valley. Coolant sitting in these pockets for years wears away at the already sub-grade aluminum usee to make these engine blocks and wears a hole through right to the main oil galley.

Some owners have had the block patched with success by TIG welding plates over the problem areas. It is a big project to fix it though. Assuming this is the problem.

[chris williams]

Difficult to tell from the picture but as others have suggested it could be a case of block rot. I recently did an article in the club magazine about this having had an engine 'chopped' in half to see the main failure location. If nothing else this picture gives an idea of where to look.
58309

[Josh]

Difficult to tell from the picture but as others have suggested it could be a case of block rot. I recently did an article in the club magazine about this having had an engine 'chopped' in half to see the main failure location. If nothing else this picture gives an idea of where to look.
58309

THANK YOU for doing that.
Makes it very clear to see where the rot occurs. Also, just need to see the cross section of a PRV.

[eight8toy]

Difficult to tell from the picture but as others have suggested it could be a case of block rot. I recently did an article in the club magazine about this having had an engine 'chopped' in half to see the main failure location. If nothing else this picture gives an idea of where to look.
58309

Would it be possible to add this cross section part to my current PRV so that I can have a V8? Asking for a friend....

[chris williams]

Would it be possible to add this cross section part to my current PRV so that I can have a V8? Asking for a friend....
Very good but the V8 PRV already exists.
Chris

[baseball_fan]

Life has slowed down a bit so I think I ready to try and find a solution to my problem. I spent a lot of time looking up engine block rot, valley of death etc. I did find a few youtube videos on cleaning the valley but no unfortunately no videos on Delorean engine block rot repair. Also there were a lot of posts suggesting TIG welding using aluminum. I would like to find more information about doing the TIG repair, obviously I would hire a professional to do that. I have some more questions if anyone has an opinion they would like to share I would appreciate it.

1) If the TIG welding was professionally done, would this project be worth doing or should I look at getting a different motor? Previous posts about TIG welding is giving me mixed signals on if this process works long term. Delorean has about 25,000 miles on it
2) What degree of difficulty would there be in removing all the necessary parts and then putting it back together?
3) Previous post suggests that it can take around 8 hours to get down to the valley of death...is this accurate?
4) Other posts suggest that all the corrosion would have to be removed in order for the best results, what is the best method to remove corrosion other than cleaning it thoroughly?

I will probably have more questions later. I'm trying to get as much information as I can, thinking that it may be best to hire a mechanic on the side to help with the project, they get it welded, then bring back the mechanic to help put it back together.

[David T]

To do a weld type repair involves taking the motor out and all apart so most of the attempts at repair do not use welding. Any repair requires removing all rot since you can't get anything to stick to rot. Most repairs consist of preparing a small metal plate and epoxying it over the hole. To get a good repair you need to get a clean surface to attach the plate to and the proper epoxy that can take some heat and pressure. Most repairs do not seem to hold up, some do. I think technique has a LOT to do with it. PJ Grady has done a few and has achieved mostly good results.

[Drive Stainless]

I can weld it with only the intake manifold and water pump removed, but are you near DC?

Another possibility is the oil plug located almost directly below the water pump. It seals with a copper washer, and if it leaks, it will leak massively.

[David T]

If you weld it without taking it apart you risk setting the oil inside on fire and getting dirt and slag inside. Not a good idea. Also you must preheat the entire block so you don't build in stresses from welding. Hard to do when it is assembled and in the car.

[Drive Stainless]

If you weld it without taking it apart you risk setting the oil inside on fire and getting dirt and slag inside. Not a good idea. Also you must preheat the entire block so you don't build in stresses from welding. Hard to do when it is assembled and in the car.


Have you done it before, David? I have.

There is no oil near the weld if you clean properly. There is no dirt near the weld if you clean property. There is no reason to pre-heat the entire block to add a 1"x1" square of sheet aluminum. There is no slag in TIG welding.

[Ron]

Life has slowed down a bit so I think I ready to try and find a solution to my problem. I spent a lot of time looking up engine block rot, valley of death etc. I did find a few youtube videos on cleaning the valley but no unfortunately no videos on Delorean engine block rot repair. Also there were a lot of posts suggesting TIG welding using aluminum. I would like to find more information about doing the TIG repair, obviously I would hire a professional to do that. I have some more questions if anyone has an opinion they would like to share I would appreciate it.

1) If the TIG welding was professionally done, would this project be worth doing or should I look at getting a different motor? Previous posts about TIG welding is giving me mixed signals on if this process works long term. Delorean has about 25,000 miles on it
2) What degree of difficulty would there be in removing all the necessary parts and then putting it back together?
3) Previous post suggests that it can take around 8 hours to get down to the valley of death...is this accurate?
4) Other posts suggest that all the corrosion would have to be removed in order for the best results, what is the best method to remove corrosion other than cleaning it thoroughly?


1) You really need to know exactly where it's coming from first...follow Dana's suggestions (http://dmctalk.org/showthread.php?16914-Need-help-with-source-of-major-oil-leak&p=239668&viewfull=1#post239668).)
2) Same.
3) It shouldn't take anything like 8 hours to get to the VOD...
4) After a thorough cleaning, the welder will dress it up the way he wants/needs it to be.

[David T]

I have not done a welded repair to a PRV block but I have repaired cast iron blocks from other cars. Similar procedure except you are welding aluminum. Just the process of preparing the weld makes a lot of dirt from the cleaning and grinding. The "slag" is was referring to is all of the dirt you will generate inside from the heat consisting mostly of burnt oil and dirt because you can't clean it well enough to get rid of it all before welding. As for pre-heating, it is just standard practice when working on a large piece so you don't concentrate stress into the piece from thermal expansion as your weld cools. Don't let me stop you from trying and let us know how it works out. As of now we don't have a good way to repair this problem so if your repair works it might become common. At the very least I would suggest changing the oil very soon afterwards to remove any contamination you may cause. Also tell us all of your welding parameters like the type of electrode, your voltage, heat, gas, type of filler rod and aluminum plate, what you did to prepare the area, etc so it is repeatable.

[Drive Stainless]

I have not done a welded repair to a PRV block but I have repaired cast iron blocks from other cars. Similar procedure except you are welding aluminum. Just the process of preparing the weld makes a lot of dirt from the cleaning and grinding. The "slag" is was referring to is all of the dirt you will generate inside from the heat consisting mostly of burnt oil and dirt because you can't clean it well enough to get rid of it all before welding. As for pre-heating, it is just standard practice when working on a large piece so you don't concentrate stress into the piece from thermal expansion as your weld cools. Don't let me stop you from trying and let us know how it works out. As of now we don't have a good way to repair this problem so if your repair works it might become common. At the very least I would suggest changing the oil very soon afterwards to remove any contamination you may cause. Also tell us all of your welding parameters like the type of electrode, your voltage, heat, gas, type of filler rod and aluminum plate, what you did to prepare the area, etc so it is repeatable.

I don’t need to try because I’ve already done it, and it works, and it’s very easy for someone who welds aluminum. There are no special tricks.


Sent from my iPhone using Tapatalk

[baseball_fan]

I can weld it with only the intake manifold and water pump removed, but are you near DC?

Another possibility is the oil plug located almost directly below the water pump. It seals with a copper washer, and if it leaks, it will leak massively.

Unfortunately, Washington DC is 800 miles away. But you feel in your experience that TIG welding an area of block rot on a PRV engine is a good, long term fix for the car? I think what's concerning me is like many other Delorean repair projects things typically go wrong, and the size of the project seems daunting to me.

[Drive Stainless]

Unfortunately, Washington DC is 800 miles away. But you feel in your experience that TIG welding an area of block rot on a PRV engine is a good, long term fix for the car? I think what's concerning me is like many other Delorean repair projects things typically go wrong, and the size of the project seems daunting to me.

You don’t actually weld the *area of block rot*; you weld above it and cap the hole, so to speak. The area of block rot will stop rotting once this is done because the area will become bathed in oil rather than a collection pool for water and dirt.

The cast aluminum welds readily when cleaned with a quality aluminum cleaner. This is what I use:

https://www.tenaquip.com/product/al-weld-o-qt-size-alumcleaner-866-1050

I have no reservations about welding this area for a long-term fix using TIG.


Sent from my iPhone using Tapatalk

[Josh]

If I only lived 800 miles from Matt, I would be loading my car up on a trailer and sending it his way if he says he is available.

This is not a small undertaking and there are only a few people in the world that have experience with this repair.

You can try to source someone locally but two things will happen:
-They will refuse the job as it is an obscure repair on an obscure car
-They weld it together and it still leaks as they are not familiar with the material the block is made out of (very poor aluminum alloy)

[DMCMW Dave]

We've got a great welder in our area who has done a couple of blocks for us. We trailered the car to his shop, he did the work right in the trailer. I agree with Matt, if you know what you are doing this isn't a huge deal.

Whatever you do, don't waste your time with crud like JB Weld in this instance.

BTW - I missed that cutaway photo when it was posted. That's a GREAT illustration of the problem. The hole at the top center is the main oil pressure galley feeding down into the main crank bearing. If the rot goes sideways into the oil line you get oil all over the street. If the rot goes straight down you may not notice it until you get rainwater in the oil (or - worst case I've see - seeds left there by mice!).

[baseball_fan]

Just a quick update on my car. I was able to find a very experienced welder who was able to do the aluminum tig welding repair. He wanted it trailered to his shop so with holiday season and weather it just took a bit longer to get the project moving. I was expecting like a large hole or crack that needed to be repaired but one of the 4 "deep pockets" seemed to be "pitted" for lack of a better term. It was nothing that would show up on a photo, but if you stuck your finger down there it felt rough, while the other 3 pockets where relatively smooth. The welder also confirmed that he felt the pocket was compromised, and other 3 were not (I guess he could tell by how the welding process was going). Of course he welded all 4 of the deep pockets. The welder also took care of cleaning the area, which he said was much more time consuming than the actual repair itself.


The car is running normally and not leaking. The project seems to be a success but I realize I really don't know for months to years to come. I wish to thank everyone who contributed to the discussion.

[David T]

With a repair like this it is VERY dependent on the skill and technique of the welder. Sounds like he knows what he is doing. Consider doing an oil change soon to remove any junk that may have gotten into the motor from the repair.

[Citizen]

Just a quick update on my car. I was able to find a very experienced welder who was able to do the aluminum tig welding repair. He wanted it trailered to his shop [snip].

This is a little off topic, but related only because you mentioned trailering your DeLorean. I am interested in purchasing an open type auto-hauler trailer that will handle a DeLorean. What trailers have others successfully used (width, length, weight and capacity, number of axles, tongue capacity, etc.)?

Or, can anyone cite a particular brand and model of a trailer they have used successfully to haul a DeLorean (or other small car)?

Thanks in advance and congrats on a successful repair of your car.

Thomas

...

[David T]

Probably should have opened a new thread. I have successfully used a tow dolly but you cannot back it up and the car must have plates and insurance and if it is an automatic you must put it on backwards or remove the half-shafts. With either the 5-speed or the auto you need good tires. With a trailer you can tow it in any condition. Getting an enclosed trailer is great because you don;t have to worry about the weather but you need a large tow vehicle to handle it. The thing you must check is width, a Delorean is a wide car. Any car trailer can handle the weight and the length.