I.O.R. 2.5cc DIESEL RESTORATION PROJECT

Here's the engine as we received it looking rather worse for wear.

Let's get him dismantled and see what's required to breath new life into him.

Well there's quite a bit of work needed on this old boy.

Photo of the crankcase left lug showing the serial number of this engine.

We have started with restoring the cylinder head as it fitted in with a few other engines which required the same treatment.

Here's the main case and front housing all cleaned up.

Followed by the cylinder liner and back plate, all cleaned and ready for the next step.

A quick test assembly to see how it looks, not too bad so far.

Now we'll get on and make the tooling to rebore the cylinder and make the new piston and contra while we wait for the new crankshaft bearings to arrive.

Well the bearings have now arrived so here we have the front housing reassembled with the original crankshaft and a pair of new bearings. The prop driver is also cleaned up and reused, but we have made a new original spec prop washer and nut.

And here it is test fitted up. We have ordered a set of new original style slotted pan head screws and will replace the cap screws once they have arrived.

Here we have the cylinder liner with all the old parts stripped down and ready for replication and final fitting/reassembly.

Here's the new conrod and gudgeon pin all finished and ready to go.

Replacement piston and contra piston, made and ready for final machining to size and fitting to the restored cylinder liner.

Here we have the finished cylinder liner all nicely lapped and ready for the new piston and contra to be final machined and fitted.

Piston and contra all finished and fitted to the cylinder liner.

And ready to be refitted to the crankcase.

Progress so far..........

Now we'll get on with the rear end, starting with manufacturing a disc drive pin as the original part was not inside the engine when we pulled it down, so we have to assume that at some point in this engines history it has suffered at the hands of Harry Homer, or is possibly a conglomeration of original parts of various different original engines assembled by someone to look like a complete engine. This would explain a number of inconsistencies we've noticed in carrying out this restoration.

Here is the new disc drive pin we made based on the parts which were with the engine. This engine is basically a Webra Mach1 clone so we have made the pin in accordance with the same principal, having it fit into the big end journal which had a hole already there, ready and waiting. The other end will locate into the pre existing hole in the induction disc.

And fitted.........

Now we'll move onto the backplate restoration.

We have cleaned out the intake tube hole and cleaned up the disc running face as it was quite less than ideal for a good operating seal.

Here we have the replacement disc pin we have made to remedy what we believe is a not so good original design which had the original aluminium disc running straight in the aluminium back plate, which had worn quite badly because of this. So, bit of a rediesgn solution required, but, how can we do that and still keep the external aesthetics looking original? 

We have made the replacement pin to be a screw in set up and have tapped the existing 2mm pin hole in the backplate to M2.5 x 0.45. This allows us to secure the new disc on a hard pivot point which gives smooth and reliable long term service. With doing this we extended the end to protrude out the back of the housing the same distance as the original pin had, so we can now refit the redundant shut down spring and keep the engine looking original on the outside while being much improved on the inside where it matters.

Test fitting of the new disc pin set up.

Now we'll make the new disc valve.

New disc valve and pin all ready to go together on the original restored backplate.

Now lets make a new spring retention clip and refit the shut off spring to complete the aesthetic external look.

O.K. so not far from finished now, just the venturi insert and N.V.A. left to do.

Venturi all finished and fitted up. Engine is based on the 1958 variant according to our information and the majority of the parts that were in this engine.

These are the needle valve assembly parts that were with the engine when it arrived into out possession.

Well, not much useful there but let's see what can be done.

Having sorted out the parts which we can recover to reuse we will get on with making the remaining replacement parts for the needle assembly.

Parts we have cleaned up to reuse.

Parts that cannot be reused as they are bent.

We will make a new fuel inlet nipple, needle carrier threaded tube, locknut and a new needle.

Needle valve parts all finished and assembled back onto the engine.

Ok so here he is all finished and ready to come to life. Now where'd that fuel bottle get to?

Off to the test stand we go......................

First pop test run.

Hot restart test run.

Here is a photo from our archival information which was our main point of reference in the restoration of this rare Romanian 2.5cc diesel Webra clone.