Engine mount studs & plate on body

[jb2000]

Over a decade ago a main dealer changed the clutch by hanging the engine on the timing-belt end engine mount (engine should be hooked to a hoist!). In so doing they sprung a joint and gouged the paint quite badly.

Likewise the main dealer did similar "hang on the mounts" when doing the timing belt and again gouged the area using a crowbar to lever it back up.

Sadly I thought the area was dry so it got left bare... crazy.
In reality it is a rain path, with undercoating the other side, perfect "rust bag". Whacking away with a hammer I forced a hole.

It appears I need to support the engine properly, remove the body-painted C bracket, cut out the bad metal, weld in new metal, weld in a new bracing panel for the underside, weld in two new M8 weld-in studs through the "ensemble".

Anyone any comments?

 

[jb2000]

Oh, those other bits of rust in the topside picture are just debris from whacking away with a hammer.

 

[jb2000]

Capillary action... dontcha love it, it had wicked between the lot, down & left...
- 1.2mm steel with the M8x20 studs in it
- 0.8mm steel going to the left
- 0.8mm steel for the body

Some more cutting and clean up to do.

Then panel beat new layers, probably plug weld the three together near the centre and shape the three over an anvil to get an identical fit. Pity the factory did not just use one thicker piece of steel in that compound curve location.

Fortunately the engine mount C-bracket just contacts at one spot which just needs to be flat at that point. Rest just needs to fit the 'ole.

Serves me right for staring at it for over a decade... ruddy fool.

 

[Blurk99]

looks like a bloody awkward fix...

 

[aametalmaster]

I can't stand dealers and so called mechanics that do more damage to surrounding areas while working on the car or truck. It never fails a few years down the road something will fail because they touched it and it never had anything to do with what was broke in the first place...Bob

 

[jb2000]

> looks like a bloody awkward fix...

It will be tedious to fix.
I had assumed it was like the previous car which just used 1.5mm steel around the engine mount, flange welding back to 0.8mm surrounding sheet as necessary.

Sourced the exact style of stud from the USA (Japan car, Hiroshima body, Osaka engine).

The white C-plate around the black engine mount (top photo) actually has a leg which drops down to the studs. The stud holes are very oversized, looks like someone assumed a far bit of tolerance. So the only critical point "in 3 dimensions" is the angle and position of the small stud area.

The 1.2mm steel had only two soft radius bends so a case of patience.

I do not believe the 3 plates were tightly stamped to the same compound curve, once the top steel corroded through it filled up with water and went mental. Only 4 small spot welds, 2 for the 0.8-to-0.8, 4 for the 1.2 to 0.8 (ie, not through the 3 thickness).

 

[jb2000]

aametalmaster, indeed.

The favourite trick on the car previous to this was to use 20w50 oil when it called for 5w30. You could hear the oil pump whine, the engine was prone to sludging, the oil strainer clogged - well you can guess the rest.

A lot of dealers put the wrong oil in deliberately as it is very lucrative, I think they caught VW & Mercedes still using 20w50 in UK & USA not that long ago.

Worth endoscoping modern turbo diesel oil pickup strainers because it is a common cause of first turbo then main bearing failure and huge bills. The cheap USB endoscopes on Ebay have great pictures, lousy light - DIY a light.

 

[jb2000]

Well, all off pretty much. Run out of consumables.

There are two dark brown patches re running-down-plate & running-left-plate, so looks like it will be a bigger hole soon.

Interestingly the area is a lot flatter than it looks, there are two distinct defined bends just visible right mid/bottom and top left, with very little compound curve.

 

[jb2000]

Well, all cleaned up.

The running-left plate.
The seam on the left DOES have corrosion in it, not quite brown, not quite surface rust. Topside the seam has a running crack with a brown stain and is on a water route. The sealer is getting old in a few high places in the engine bay and either no longer pliable or losing adhesion with grey primer exposing. The plate was also incorrectly welded, a spot-weld into thin air, with an air gap of about 1/16" if not double that creating a nice water pocket.

A second job to do once this is tidied up.

The dropping-down plate with studs on.
Corrosion at the bottom underneath this plate in the top body sheet was very superficial and cleaned up to clear bright steel with barely a pin prick. Will use an engraver tip and kurust on that area to get things properly clean.

Just got to work out a cutting route next.


Aside: quite a few cars have an "ash tray" at the top of the front wheel arch to fix the top of the plastic wheel arch shroud. Beware main dealers love to leave out the top shroud peg, so you have all the spray (salt) coming off the tyre and up through this hole which if your drive is at a severe angle will not drain correctly as soil & salt build up. I know this because part of the "ash tray" is in corroded pieces at the bottom of the side bumper! All the lower plugs in, had run out of plugs by the time he got to the top. Sigh.

Strangely it appears to be a generic panel used on many models with a good third of it sitting in mid air doing absolutely nothing either structural or functional with numerous clip points. It can however track corrosion completely hidden into more important areas. So worth checking missing pegs.

 

[jb2000]

Oh... what a pig.

It is not 0.8mm, it was 0.7mm...
... except on the RHS where the "duck-bill-stretch" had made it **0.52mm**.

I am unsure whether 0.7mm is cheaper on press-tonnage or easier re stretch over 0.8mm? I really wish they would use thinner steel for all the internal brackets, lighter materials for all the internal junk and just draw the line at 0.8mm at rust-prone areas.


Got the big hole filled, welded 3 times.
#1 on top, #2 alongside to boost the thickness of the metal, #3 from below. I wanted the area to be a good bead above & below for strength, there are 2 more plates to add.

Anyone know what thickness BMW use on E46 wheel arch "inners"?

 

[jb2000]

Ugh... talk about complicated shapes.

Top & Bottom part shaped & Lincoln Innershield gasless welded.
- Seam welded 0.52-0.70mm car body to 0.8mm patches
- Plug welds at the frame rail curve (topside) perfectly tight using M5 bolts

Some welds need a light grind just to tidy, not taking much off as thin.

Played with copper too.
- Bridged a small 1/8" gap by copper plate behind and starting on the copper
- Likewise welded right to edge by starting on copper sheet and moving back, works wonderfully, just a bump to grind off. Wish I had learnt that earlier.

Weird...
Topside photo, LHS by the plastic bags over the p/s hoses, the bit that drops down to the frame you can see an indent - perhaps a breaker bar to manipulate the engine mount around after doing the timing belt. It is just the right kind of shape.

LHS seam sealer cracked topside.
Couple of orange dabs visible, will need exploring. Seam sealer clearly dries out in the hotter areas (19.8yrs old) high under the bonnet and near the exhaust.

Once LHS is done it is the reinforcing plate layers... capillary action and layered steel... right nightmare.

 

[jb2000]

Could not find a time machine, but after many minutes...

Rusty spot weld base - replaced by 1.2mm Zintec.
Complex #1 & #2 pieces (0.7mm each) - replaced by 1.5mm Zintec which required slotting to handle both shrinkage and a lot of spiral twist the photo hides. Then backing anvil & hammer to get the wave accurate across all pieces.

Welds not ground down, they will be, too tired tonight.
Used 5mm bolts to clamp the plug weld holes tight, undid one at a time, plug welded with copper sheet behind and a tiny magnet elsewhere, worked superbly.

Last is a vertical 1.2mm patch from the bottom frame to the new M8 studs from USA... hopefully that goes ok, utter pig of a job.

 

[Blurk99]

that looks like you've done a horrible section very nicely - i wouldn't bother grinding the welds, volvo never did on a V40 i used to own!

 

[jb2000]

Thanks, the welds are a bit bumpy - will level them uniform at least.

Last bit...
- "Drop-to-Bottom" reinforcement, from M8 studs to frame rail.
- Concave, twist, curve - and lots of them.

Ok, single 1.5mm... or single 1.2mm...
Failed - the plug welds would be spanning air, just too stiff.

Ok, double 0.8mm...
Perfect - soft enough to get a perfect fit, stiff enough all together.

Will use multiple M5 bolts to get everything locked super-tight & plug weld.

 

[jb2000]

Backing #1, 0.8mm of the M8-studs-to-bottom-frame-rail piece.
- Plug welded, backed off bolts to check absolutely perfectly tight all over.
- Zintec, with zinc spray, with galvafroid between the sheets.

Backing #2, 0.8mm to do tomorrow on top.

 

[jb2000]

Got #2 done... lots of plug welds...

Not particularly pretty, but functional and far better than before.

Left of the underside photo, strut turret base.
- On the underside you can see the chunky seam welded patch.
- On the topside nothing is visible but smooth metal
- Got a Draper "Dremel" with Proxxon grinding stones

Waiting on my M8 weld in studs from the USA.
Just softening the welds to a uniform soft bump, do not want a ledge.