Patricia A. Mayer's 3.0 CS / Paul Cain's Fjord project / The 300 mile Test Drive / VIII / Final Punch List

[tightbox]

Just realized I should google the VIN for answers to my questions.

Did you use dry-ice blasting to remove the old Thixo-Tex black aftermarket undercoating?

My very similar (but slightly higher mileage) survivor was coated by Ziebart, and I've wondered what the best method is to clean it up - or if I even should. Your car looks remarkable underneath, so I'm now leaning toward cleaning it!

 

[paul cain]

@Erik. Good question. The rust is about what I expected in the lower front fenders (bad). There are areas on the edges of the floor pans where the stone guard / rocker schutz has pealed away exposing raw metal. The pans are all intact and this will need surface treatment and reschutzing. This peeling also occurred in all four corners of the sill ends. The right front fender lower section is toast. I am going to replace both of these lower panel sections and cut open the end caps on the lower sills to really see what is going on with a digital Bore-a-scope. I will have some close ups of this in future chapters as I have a plan to crushing any rust issues with some comprehensive prep and modern paint sealing chemistry. Stay tuned.

 

[paul cain]

@tightbox The key to cleaning the undercarriage is breaking down the dirt first. We have a phenomenal local detailing service that does 'chassis cleaning' He has perfected the hot pressure steam / blaster to not damage the undercarriage finishes. Before I bring it in to him I soak the entire undercarriage with diesel fuel. (its incredibly smelly and messy). This breaks down the grease. The detailer puts the car on a lift and goes in with his hot pressure blaster and spends 2-3 hours on the car. Not cheap, but a great starting point to see what is really there. Whatever Thixo-Tex juju concoction was on there is now off and it is back to the OEM surface finishes. This is most notable on the wheel wells.

I use dry ice in really, really selective areas like these throttle bodies: https://bringatrailer.com/listing/1985-bmw-m635csi-33/ where there are very complex mechanical assemblies that are visible. Its also very pricey.

 

[paul cain]

A massive thank you to @Gary Knox for the OEM rear muffler. As soon as Gary posted it was available, I hit 'mine' as anything that Gary brings up for sale will be top drawer. Note the PVC protection that was a part of his comprehensive packaging. Thank you @Gary Knox !

In the background are the rest of exhaust collection from BTS-Autoteile. Center 'bed warmer' mufflers are allegedly still available from BMW at ~$239.00 USD. One is on the way, the last piece in the ausspuffen puzzle.

 

[Gary Knox]

Thanks for the compliment Paul. It took me several hours and thinking through several options to finally settle on a shortened 3" PVC connector to protect the inlet for the muffler. Glad it worked out well.

 

[eriknetherlands]

....

. I am going to replace both of these lower panel sections and cut open the end caps on the lower sills to really see what is going on with a digital Bore-a-scope. I will have some close ups of this in future chapters as I have a plan to crushing any rust issues with some comprehensive prep and modern paint sealing chemistry. Stay tuned.

You do not actually have to cut it open as there are plenty of openings on the inside of the sill,just remove the white plastic caps that were there for wax injection originally. Also the hole for the bolt of the lower belt anchorage is opening into the sill. Furthermore you can go into the lower B pillar, and even u.der the rear seats access the critical rear of the sill.
Saves you some welding up if everything turns out ok.

 

[paul cain]

@Erik good question and the perfect segue to our first topic: Crushing the end of sill rust on all four corners.

Here is the starting point after cutting away the lower fenders on all four corners. I am very pleased with the condition underneath these fenders. There is some metal replacement we will be doing and we won't know how big those cuts will be until after walnut shell blasting all four corners. Replacement sheet metal has been sourced (W&N) and there are 8 steps before we will be welding those into place.

Patricia Mayer had the car zibart'ed early on and this really saved the majority of these inner / lower sills. We will be uploading some images of this virginal yellow waxy coating that remains intact on these inner most sills. This condition is a colossal relief. For now we want to thank @Teutonic (PCA & BaT) for the use of his Depstech DS450 Bore-A-Scope, sending it deep into the front and rear entry points on both sills. Here is one image about 18'' in from the D/S rear sill. Florescent orange paint is guidance / instructions to the media blast nozzle operator to stay within the lines.

We've decided to leave the car on the stands. Its at a metal fabrication and machine shop and we really do not want to pollute the surroundings. A massive thanks to @Mike Pelly for the use of his portable spray booth that you see collapsed on the foreground of image 8419. We are going to do more plastic wrapping on the car, this combined with the booth we should be able to blast hard from any angle. This shop is also handling the welding required on the chrome bumper conversion. Introductions to follow.

Next step is to blow some holes in these sills and truly assess reality. Stay tuned.

 

[teahead]

wow, that was quick!

 

[paul cain]

I was not totally in the camp of Ziebarting 1970s cars. Boy was I wrong. Here is the first Bore-a-scope result of a long pass inside the lower structural sills on Patricia Mayer's 3.0 CS Preservation project. The yellow wax is still soft and you can see the dragging marks from moving the bore camera along the sill. I am elated at the condition of this critical unibody element on this project.

 

[paul cain]

No need to adjust your TV sets..... the above video looks to be a routine Esophagogastroduodenoscopy. Shockingly similar to the waxy inner lining of a Coupe lower sill.

Someone commented earlier if there was a difference with the rust protection at Karmann starting in 1974. Based on the 1972 build date of my earlier coupe where I completely removed this outer sill and replaced it, the answer is yes. In 1972 there was almost no grey primer on these inside surfaces (perforated inner panel), just a light surface rust. Patricia's '74 had an early 74 build date but the primer coverage is much more consistent and the amount of stoneguard / rocker schutz underneath the car is thicker than earlier 3.0's and much thicker than 2800 CS's.

 

[pickman]

During my refurbish of the 73 E9 I replaced the front bumper supports back to the 1972 style. It pulled the front bumper closer to the body and lost a few pounds of iron. The 72 style supports are hard to find so I made them for about $70.00.

 

[JFENG]

rust protection at Karmann starting in 1974

finally, something that makes post 1973 coupes more desirable, besides power window electronics.

 

[paul cain]

When you make parts out of water absorbing press board and put them under the front suspension, they usually do not last too long. I love it when boxes arrive from Germany. This just arrived today. I've only seen two in past 41 years of playing with coupes. This will go into storage for now to reappear on Patricia's car in 2022.

 

[JFENG]

When you make parts out of water absorbing press board and put them under the front suspension, they usually do not last too long.

Suggest you have someone pull a fiberglass mold of it first so it’s possible to make up repro a that do not absorb water for us ordinary E9 owners. If necessary, I would contribute to the effort for a credit towards a GRP part later on.

 

[HB Chris]

The repros already exist and are more durable.

 

[adawil2002]

That under panel was the first part I was glad to remove throw out when I bought my CSi. It traps water & dirt helps rust the lower nose.

 

[HB Chris]

But it keeps subframe and suspension bits from getting rock chipped and the old one was paper based.

 

[paul cain]

Came across another BMW Werkes photo I've never seen before -from the E9 final assembly line. The guy at the front of the line appears to be getting ready to install the windshield. Can you imagine doing that every hour of every day?

 

[Stevehose]

After that he’ll have to put the hood grilles on then drink a cold one

 

[paul cain]

Image 1 Progress on fitting the early chrome bumpers. A big thanks to @tom Rakestraw for measuring the precise height of his rear bumper on his city pack CSL. Here is the key dimension - 30 mm.

Image 2 & 3 I fabricated some quick centering pins that work great for one hard 'smack!" method. The method is precise: place bumper to body, inspect gaps and position, measure, inspect, remeasure, stand back 30 feet and inspect. Then SMACK! and you get your center punch position on where to drill the body. Three smacks on the right side bumper and three on the left. Then drill. Then reassemble bumper.

Image 4 Bumper and bumperettes ready to go. All the mounting bolts have been thread chased.

Image 5 is the position of the side of the early chrome bumper at the swage line.

Image 6, 7 & 8 This is the metal work that has been done to date -prior to this bumper fitting.

Today was the first 'dry fit' of the donor bumpers to the '74 body. A few nights rest and then I will go back and start final fitting, grinding for the correct gaps and fitting the bumperettes to the body.

Last three images are of the first dry fit.