What do I use to clean the engine to make it look new

[corascate]

Hi all
What can I use the clean the engine so that it looks “new” the bike is a K7 and it is not filthy by any means, but it could look much better,
And also I was looking at triggers build for less than a grand, what are you using to polish the brake backplate etc it’s turned out luverllly.

[JamesH]

The only way to get the engine to look ‘new’ is to pull it from the frame, rub-down and carefully respray either as a complete unit (not ideal and slightly frowned upon)  or when fully disassembled for a strip / rebuild.

Sorry - I know the answer you’re looking for is probably less work...having said that, with the ending in frame you can completely degrease and clean the engine with brushes / degreaser - but will need to strip quite a lot off first to make it noticeably worthwhile.

A plastic brush like this in conjunction with a spray degreaser will work well to get in between the cooling fins on a 750...

[corascate]

i had a feeling that may be the response imy plans for the bike are to get it running properly to a good roadworthy standard and then remove the engine and do a full rebuild.
as it is a bit rattley when i got it running first. so i will leave it as is for now and then do as you suggest, so i will concentrate on the wiring and rewelding the centre stand mounting brackets.
when it comes to it and its stripped down, are those ultrasonic parts washers any good at the job?
thanks
steve

[AshimotoK0]

Difficult one. The pros would have the bare crankcases chemically dipped to remove paint and impregnated oil then soda blast or whatever but this requires a total strip down an the cases send off to a specialist for chemical dipping.

It also depends on your crankcases. If the paint is still fairly good and well adhered I have seen people sand down any areas that the paint has lifted and degrease with brushes, Scotchbrite, degreaser etc etc then solvent wipe and paint and the results are certainly accepable. One thing you deffo want to avoid is any abrasive media being left inside your engine as it can get into every nook and cranny and even embed itself in the aluminium only to release itself possibly once the engine is run.

One thing I do on my Honda twin,  non-plain bearing engines,  is to assemble the engine (after removing any oil with degreaser, pressure washer) with no internals,  and seal up every point of ingress of blast media with old  components, oil seals with their holes filled with something). I then pressurise the case to a few PSI via the engine breather and test for any air leaks around the joints with a solution of dish soap (as the Americans call it) brushed on every joint. One it's leak free and holding pressure I then bead blast it with ultra fine 0/44 glass beads that produce a really fine finish. Then pressure wash and wash in acetone. Then brush with weak nitric acid/ sulphuric acid mix to remove surface oxidation, thoroughly washed off then painted.

During the lockdown I have no access to blasting cabinet so using good old fashioned elbow grease as detailed above and also described by Jamesh on my Cb500/4 engine. It takes bloody ages but needs must in these difficult times.

Here is one of my CB250K0 engine .. no internals before and after blasting

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[AshimotoK0]

Re : ultrasonic cleaners .. they are great for cleaning carbs etc and they dislodge dirt etc in the internal galleries etc but not everything they are cracked up to be and require additional equipment to be employed in conjuction with them (i.e media blasting)
For example if you have water ingress into carbs that causes the white horrid coating on the float bowls etc, an ultrasonic cleaner won't touch it.  I have a massive industrial one that I got from work and repaired and it's great for general cleaning of part prior to bead blasting etc. Be sure to use proper fluid designed for delicate aluminium parts though in  de-ionised water (Eurocarparts is the cheapest place for DI water)
Beware of some cheap Chinese (direct from China)  ones that self distruct after a short time of use. I think places like Allendale do Chinese ones but vetted for decent build quality. They also sell the specialist cleaning fluids.

The test for a U/S cleaner is to put a bit of thin aluminium foil in it for a few minutes and then remove it and hold it to the light and it should be peppered with tiny holes if the U/S action is working properly. The cavitation bubbles punch tiny holes in it.

[SteveD CB500K0]

If those are through-plated-holes in the exhaust ports Ash, you are in trouble

[AshimotoK0]

If those are through-plated-holes in the exhaust ports Ash, you are in trouble

No trouble  ..it was backed with  a 1mm silicone rubber sheet

The fasteners/  cam bearing  covers / alternator cover  and camshaft were just old scrap items... note the cam has a broken off shaft that the auto advance fits on to... it was a perfect cam until DK shipped it in a polythene bag with no other packing/padding and the shaft broke off in the post where the dowel pin fits  .

[MrDavo]

As I don't have access to blasting or washing plant I have to use James' brush and solvent approach. And time, lots of it. ...

When I restored my barn find CL450, I washed and brushed the unpainted alloy head and barrels with first petrol and then brake cleaner, I used a fine modelling brush to get in between the fins, while squirting in the brake cleaner from an aerosol can, held close up to use the pressure to shift the crud. Expensive, unless you can get it cheap, but it worked.

The crankcases I thoroughly washed in petrol, using a tin can and a small paintbrush, the old blunt screwdriver is for persuading old gunk between the fins to come out.



I then used, wearing a mask I bought online (that the wife now uses for shopping!), Magic paintstripper, with extra deadly fumes, applied with a brush, to get the remains of original yellowed laquer off where originally applied on the polished parts of the cases. Then I mixed up some baking soda I bought from the corner shop with a little water, and scrubbed all the nooks and crannies with an old toothbrush to degrease everywhere before painting.

When I was finally happy I used Simonize silver VHT from a rattle can. I heated the can in a sink of hot water as it was the middle of winter.



Finally, I polished the alloy cases on a bench mounted polishing wheel after getting the remains of laquer and blemishes out with fine wet and dry. I used polish from a block I bought at an autojumble years ago.

The (nearly) finished result.

[Spitfire]

I spent many a happy hour with petrol, paraffin, Brillo pads, lolly sticks, Dremel with little wire brushes, cleaning my engine before painting it with VHT paint. It was worth all the effort in the end despite the stubbed and sore fingers.



Cheers

Dennis

[MrDavo]

I like the creative use of house bricks and wooden blocks as an engine stand.

Mine is the Trigger version.

[AshimotoK0]

Those engines look simply spiffing Dennis .. you should be very proud.

Word of warning to anyone going to a soda blaster ... I went to one near me and he told me he uses the same blast cabinet for both glass beads and soda .... . I walked away because there is no real way of running the two media's in the same cabinet without cross contamination no matter how much you try to clean it IMHO.

[Spitfire]

I like the creative use of house bricks and wooden blocks as an engine stand.

Mine is the Trigger version.

I must admit that was not as impressive as my 3x2 stand that I used for the final assembly of the bike

Cheers

Dennis

[ST1100]

An associated question:
what's the preferred look on those classics?
"new, off the shop floor" or "clean, with well earned patina"?

[SPR]

I spent many a happy hour with petrol, paraffin, Brillo pads, lolly sticks, Dremel with little wire brushes, cleaning my engine before painting it with VHT paint. It was worth all the effort in the end despite the stubbed and sore fingers.



Cheers

Dennis

LMAO ... I've just walked in from touching up the silver whilst the carbs are off feeling pretty smug .......... to be presented with how it should be done !!!!

I hang my head in shame

[JamesH]

I spent many a happy hour with petrol, paraffin, Brillo pads, lolly sticks, Dremel with little wire brushes, cleaning my engine before painting it with VHT paint. It was worth all the effort in the end despite the stubbed and sore fingers.



Cheers

Dennis

I have to say that finish looks f*ing superb. Bravo.