All work on the new engine is done by the Professionals of Ol‘ Skool Customs, the big inch company or in assistance of these nice guys. Thank you very much for teaching me how to build a new engine for my Willys.

Engine block number and origin

The new engine block is probably from Swiss Army due to the blue color and because of the engine block number MD 115560. Blue colored engine blocks were replacement blocks but there was no „R“ for Replacement stamped in. Thats the actual state of knowledge. 

I also asked Harold Bergers from the Netherlands for advice. He wrote me in October 2021:

„This must be a 1958 engine from a Swiss M38A1. I found the following engine numbers on the internet:

> Zwitserland 820x M38A1 1958 / M+65000 t/m M+65819
> 57048-10-10316 motornummer MD115093
> 57048-10-10432 motornummer MD115344
> 57048-10-10817 motornummer MD115652
> 57048-10-10822 motornummer MD115743
> 57048-10-10878 motornummer MD115782
> 57048-10-10969 motornummer MD115905

So, your engine belonged to a M38A1 with a serial number between 57048-10-10432 and 57048-10-10817.“

Casting Number of the engine block SD 807895 12:

Cleaning the engine block

The engine inside was covered with this red paint or lubricant (?)

This is what the engine looked like after cleaning the complete engine block:

Crack proof of the new block – December 3rd, 2021

It’s necessary to check the block on cracks. We did that with a red fluid that permeates the cracks as you can see on the following pictures. 

Another procedure to locate cracks in the block is the magnetic field inspection. But this is more complex.

Rotes Farbeindringmittel KD-Check RDP-1, zugelassen nach DIN EN ISO 3452-2.

Das rote Farbeindringmittel wird auf den Block gesprüht und nach einigen Minuten wieder entfernt. Es dringt in vorhandene Risse ein, die anschließend durch das Auftragen einer Entwicklerflüssigkeit sichtbar gemacht werden. So werden auch Risse sichtbar, die mit dem bloßen Auge nicht zu erkennen sind.

After getting the block covered with the red fluid we cleaned it all up to use the developer fluid to get the cracks visible.
Nassentwickler auf Lösemittelbasis KD-Check SD-1, zugelassen nach DIN EN ISO 3452-2.

We were happy to notice, that the block had no cracks, so we can use it for building a new F4-134 for the Willys. This process was exciting. The following pictures show a cracked V8 Ford Mustang engine for example.

Das folgende Bild zeigt den V8-Motor eines Ford Mustangs, der zwischen Zylinder 2 und 3 kapital gerissen ist. Dieser Riss war mit bloßem Auge vorher nicht zu erkennen. Erst die Eindringprüfung mittels der Farbeindringflüssigkeit machte den Riss sichtbar.



Engine measurement – January 04th, 2022

We started with the measurement of the housing bore.


Data: Housing bore 

Standards vs. our measurements:

front: 63,5 mm -> 63,47 mm

middle: 63,25 mm -> 63,22 mm

rear: 62,99 mm -> 62,99 mm

Stay tuned for more pictures…


STATUS: December 06th, 2022| NOTICE: All pictures are taken and created by myself. Respect the Copyright!

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