Engine with block rot question

[DMC81]

So it turns out I have some block rot going on down in the valley and I will be looking for a good used engine next spring. Is my engine worth anything and if so do I sell it or am I better off to keep it for all the parts?

[chris williams]

Depends if your looking to swap it for an engine from a Volvo or from a DeLorean, also depends on what bits you get on your replacement engine (fuel/electrics/etc) condition may be unknown so you may wish to keep yours as good spares. If it were me I would keep everything (if you have the space) you can always get rid off stuff later when you know you don't need it!
Chris

[jamesrguk]

So it turns out I have some block rot going on down in the valley and I will be looking for a good used engine next spring. Is my engine worth anything and if so do I sell it or am I better off to keep it for all the parts?

Sandwich plate and sump are dmc specific and can be useful if you intend to install another variant of the PRV engine.

I'm in the same situation, but have a volvo engine to drop in which requires the sandwich plate and sump of my old engine.

Don't chuck anything, at least not till you car is back up and running with the replacement engine.

J

[DMC81]

Thanks for the tips guys, what a way to end the year with block rot.

[psahos]

How does one know it is block rot that oil is coming out ? I have a Delorean and the oil seems to be coming from the waterpump ? There is a sound also that is made like bubbles of water from the engine. When the car is turned off - oil below is dripping again from the water pump area ? So can oil be coming from the water pump compared to block rot ? I am praying tonight that it could be merely the water pump? Anyone there to respond back with good news ? This originally happen when the car was overheating and mist of antifreeze was found in the engine compartment - The fan was not coming on which resulted in this problem - but there was not oil at that time -Today - spray of oil is coming out from the area of the water pump.... Thus, should I panic ? Lou:banghead:

[DMCMW Dave]

Thus, should I panic ? Lou:banghead:

Maybe not panic, but get your bank account warmed up. . . . See PM./Email.

[Shuttleman]

I found a way to repair the block involving machining the valley. I have a complete engine that was running. I have made a swap for a different kind of engine but my original engine had corrosion that made it thru the crankcase on inspection. I could repair this engine and this would also eliminate the deep pocket collecting water and dust in the valley. But I think even if I make this engine top notch it is not worth it because I will not be able to sell it at a price that is worth the time and parts put into it.

[Drive Stainless]

I can weld a square piece of aluminum in the valley to seal the leak. Cast aluminum, even if dirty, is no problem. I'm just outside of Washington, DC if you can find a way to bring it here.

If you decide not to repair it, I would be interested in purchasing it.

[chris williams]

I can weld a square piece of aluminum in the valley to seal the leak. Cast aluminum, even if dirty, is no problem. I'm just outside of Washington, DC if you can find a way to bring it here.
Be interested to see some pictures of this repair, we tried this on mine and it did not work, the oil pressure just found the next weakest point to get out. I will see if I can dig out pictures from when we tried it.
Chris

[Shuttleman]

Welding works if the hole is thru the crankcase. And you have to remove all corrosion before inside to stop it. If the hole goes thru the oil valley it will not repair this. Also welding introduce some small distortion. When welding on a engine or transmission you have to be careful where you do it. At this place it is no problem thought and it is the good way to repair if after you removed all traces of corrosion and confirmed oil passages integrity are not compromised.

[Shuttleman]

In these photo you see corrosion making its way thru the crankcase. In the second shows after the corrosion has been removed. Oil passage were not affected so this engine could be welded on the to of the valley. It is for sale but only as an assembly (the whole engine with fuel components, accessories: alt. A/C etc... Make an offer. 468444684546846

[chris williams]

Interesting, would like to see pictures of the repair. Still searching for the ones I have! I have two engines coming over the winter with the same problem to fix (block changes) will be interesting to see if these are the same.
Chris

[louielouie2000]

I can weld a square piece of aluminum in the valley to seal the leak.

I know Farrar Hudkins had to do this a couple of times, but the oil kept finding new ways to escape. Farrar is in the process of an engine swap now. Once valley rot has set in with the PRV, there's really no saving the engine; only ways to postpone the inevitable.

[Drive Stainless]

I know Farrar Hudkins had to do this a couple of times, but the oil kept finding new ways to escape. Farrar is in the process of an engine swap now. Once valley rot has set in with the PRV, there's really no saving the engine; only ways to postpone the inevitable.

I am curious about what is happening here. The "block rot" holes that I have seen have occurred in the bottom of the deep, ~3/4"x3/4" square-shaped holes. The solution seems straightforward: cap the holes with some small squares of aluminum. But both you and Chris Williams explain that the oil will find a new place to leak from, as if the oil could blow through the cast aluminum like a stream of water through tissue paper.

Nevertheless, I am very confident that I could make this repair based on my experience TIG welding aluminum.

[Bitsyncmaster]

I am curious about what is happening here. The "block rot" holes that I have seen have occurred in the bottom of the deep, ~3/4"x3/4" square-shaped holes. The solution seems straightforward: cap the holes with some small squares of aluminum. But both you and Chris Williams explain that the oil will find a new place to leak from, as if the oil could blow through the cast aluminum like a stream of water through tissue paper.

Nevertheless, I am very confident that I could make this repair based on my experience TIG welding aluminum.

I don't think many people have tried to TIG weld a block for their fix. I'm betting that would work.

[Josh]

Farrar was just filling the hole with epoxy. It works for a while (depending on how much you drive the car) but the epoxy will just turn into mush or simply pop out.

[Shuttleman]

I don't think many people have tried to TIG weld a block for their fix. I'm betting that would work.

Yes many people have.

[Shuttleman]

46889
This is just one example from DMCH. The problem it that people do not remove ALL the corrosion. It has to be removed. It may go thru an oil valley but their is no point if you'r turning a blind eye on it. For sure it will go thru later if it's there already. You have to remove it all and make a good inspection of the wall thickness. Also corrosion never stop so another reason to remove it. Even if it's thru the oil passages there is a way to repair it but most owner are not ready to pay the price for it.

[chris williams]

I am curious about what is happening here. The "block rot" holes that I have seen have occurred in the bottom of the deep, ~3/4"x3/4" square-shaped holes. The solution seems straightforward: cap the holes with some small squares of aluminum. But both you and Chris Williams explain that the oil will find a new place to leak from, as if the oil could blow through the cast aluminum like a stream of water through tissue paper.

Nevertheless, I am very confident that I could make this repair based on my experience TIG welding aluminum.
I was unfortunate (or fortunate depending on point of view) to have one of the first engines to have this issue about 10 years ago and it was then a rather un-known. I have attached a couple of pictures of the repair I had done. The plates were TIG welded (not by me but a specialist) after the block was cleaned as well as it could be. Then coated with Glyptal paint as I have done on many engine re-builds since.
Unfortunately whilst the weld worked and held the leak just found the next weakest point through one of the 'ribs' so I just changed out the block. I have found locally an 'old school' engineering company that specialises in repairing ally components so when I get my hands on another block that's go the same issues (I have two to do this winter) we are going to have another look at repairing them. I'm sure however these can be repaired as it seems DMCH are doing and you think you can, I just wonder if it's dependant on how bad the block rot is to start with?
4689346894

[chris williams]

46896
Another picture with rot in an unusual place (not one I have done, snatched picture from somewhere) I have been investigating this for some time and am convinced TIG welding is the best option.
Chris

[cis6409]

Hi Chris that last picture there you posted is of a local owner here in Ireland ..
He has tryed welding it with aluminium rods twice I believe and both times it leaked .
It seems there s at least more than a few holes . He is now in the process of doing an engine swap .

I have been looking into this with great interest to as my valley had holes in the trenches to .. thankfully they didn't go all the way thru . A friend recommended a company in cork to try a new process of aluminium welding .
I sent the car down with valley completely stripped and he prepped the entire surface and trenches of the valley by giving it a etch of soda blast and then used a special gun to shoot molten molecular aluminium to fill the holes up..
I done this 4 or so years ago and still holding up well fingers crossed !..
It's another option dunno if anyone else has tryed it ..
But I definitely believe there has got to be a way of fixing the rot
Cheers
Shane

[cis6409]

Here's some pics of the process and how bad my rot was

Sorry about how small some of the pics are I can't get them any bigger

Cheers
Shane

[chris williams]

I sent the car down with valley completely stripped and he prepped the entire surface and trenches of the valley by giving it a etch of soda blast and then used a special gun to shoot molten molecular aluminium to fill the holes up..
I done this 4 or so years ago and still holding up well fingers crossed !..
It's another option dunno if anyone else has tryed it ..
But I definitely believe there has got to be a way of fixing the rot
Cheers
Shane
Cheers Shane,
Yes I remember now, it does seem a novel approach were they all ok about doing this with the engine in-situ? Did it worry you at all about any of the molten stuff blocking any of the oil galleries? Is there a specific name to this process?
Thanks
Chris

[cis6409]

Hi Chris
Yeah they had no problem doing it with the engine In situ in fact they didn't take the car off the trailer. They masked the entire car off very well and everything else to ..

The process is called thermal/spray welding , I believe it's also used on oil rigs and such . I think it's a variant of cold welding also ?


I didn't worry about the molten metal getting into oil gallery's because thankfully the holes were bad but not gone all the way through (apologies if I mis stated that )
I decided to do this as a preventive step to arrest the rot from going any further ..
He also filled and capped the trenches with the molten aluminium as I think you can see In the pics .

Cheers
Shane

[dmcman73]

Hi Chris
Yeah they had no problem doing it with the engine In situ in fact they didn't take the car off the trailer. They masked the entire car off very well and everything else to ..

The process is called thermal/spray welding , I believe it's also used on oil rigs and such . I think it's a variant of cold welding also ?


I didn't worry about the molten metal getting into oil gallery's because thankfully the holes were bad but not gone all the way through (apologies if I mis stated that )
I decided to do this as a preventive step to arrest the rot from going any further ..
He also filled and capped the trenches with the molten aluminium as I think you can see In the pics .

Cheers
Shane

Hi Shane, sorry for reviving an old post, but, since you had this done a few years ago, how has it been holding up on your engine block?

[cis6409]

Hi
Yes it was holding fine no issues at all it held up well. however the car is off the road for last while as Im doing a full engine rebuild. Nothing to do with the block rot, thankfully.

40 year old head gasket finally gave up through age and degradation . Compromised itself on cylinder 1 by letting exhaust gasses into coolant circuit. Took a while to diagnose cause it was a small failure on the gasket itself but in the end a fail none the less.

Hopefully she ll be as good as new when Its finished.


Shane

[dmcman73]

Hi
Yes it was holding fine no issues at all it held up well. however the car is off the road for last while as Im doing a full engine rebuild. Nothing to do with the block rot, thankfully.

40 year old head gasket finally gave up through age and degradation . Compromised itself on cylinder 1 by letting exhaust gasses into coolant circuit. Took a while to diagnose cause it was a small failure on the gasket itself but in the end a fail none the less.

Hopefully she ll be as good as new when Its finished.


Shane

Thanks for the quick reply! So no issues with the new aluminum that was applied to the block during the process, nothing peeling away? Good luck with the rebuild!

[cis6409]

No, no issues of peeling or adhesion - Once the prep is done correctly it should be good.
I don't know if anyone else has ever done this on other prv blocks, I know no one else in Ireland has done it. After weighing up the pros and cons of it, for me it was worth a shot.

I still think " normal" welding can be done to fix block rot once it's not gone to far . Welding 'Cast aluminium' is a very rare skill at least in my part of the world. Loads of normal steel/iron welders and aluminium welders but very few had any decent experience with cast aluminum which was the catch for me at the time ..

[Josh]

Here's some pics of the process and how bad my rot was

Sorry about how small some of the pics are I can't get them any bigger

Cheers
Shane

It seems like it would have been way easier just to pull the engine.