RCV58CD

[Andy J]

Have an RCV58CD which occasionally sounds like a sewing machine when turned over with a regular clicking noise. Introducing oil to the intake seems to clear the issue but the noise quickly returns.  Decided to investigate the noise as the engine has never been right after having its bearings replaced. Managed to get the crank case open after a bit of heating to the screws and resorting to the use of a dremel cutter on only two of them. Luckily no damage was done to the crank cover. 

 

As far as I can see without any real knowledge of RCV engines is that there appears to be a lot of play between the cylinder gear and the crank gear is this normal?  Certainly rotating the prop back and forth produces a clicking noise from the gears but unclear if this is the noise I heard initially.

 

Open to suggestions as to what to do next.

 

 

[Andy J]

Which way round should the con rod go?  Con rod appears to be offset so unsure if this is correct as pictured.

[J D 8]

Only use SP60 myself but looking at an exploded diagram of 58CD [ on You tube ] I would say yours is the wrong way around. 

[Caveman]

Andy, there's a video on YouTube of an RCV91 being assembled and it shows that the conrod on yours is the wrong way round.

 

Have a look here 

 

 

GDB

 

Edited May 3, 2021 by Caveman

[Martin Harris - Moderator]

Agreed - look at the offset on the gudgeon pin.  Was it assembled that way while it was clicking?  I can't think what might be causing it but if it was that way it's a distinct possibility that it was the cause.

 

I did have an odd noise from my RCV 91 - a loud catching sound during flight.  I put new bearings in about 7 years ago and it hasn't re-occurred.  The old cylinder bearing felt notchy when I removed it but went smooth again after inspecting/playing with it for a while - presumably a foreign object has got in amongst the balls but I couldn't find it.

[Denis Watkins]

17 hours ago, J D 8 said:

Only use SP60 myself but looking at an exploded diagram of 58CD [ on You tube ] I would say yours is the wrong way around. 

Agreed

The debate is inside on YouTube

And out side in your picture Andy

[Andy J]

Thanks chaps, reversed the conrod and re-assembled the engine. Seemed ok until I tightened the crank case bolts and the noise returned.  Seems to be a messing of the gears over a 1/4 of the rotation of the cylinder so wondering if the shaft is bent or alternatively the cylinder head bearing is faulty. Certainly could not detect any roughness in the gears with the piston removed so assume the compression has an effect somehow.

Edited May 4, 2021 by Andy Joyce

[J D 8]

 Try turning without plug in ? As Martin found his cylinder bearing notchy recon a change there is on the cards.

[Andy J]

Problem is what to change, cylinder head bearing, rear bearing, both gears or crank?

 

May be best to keep it for spares and fit a new engine.

[J D 8]

 Just the cylinder bearing I recon, it's the only one I have had to change on an SP engine.

[Jon H]

2 hours ago, Andy Joyce said:

Problem is what to change, cylinder head bearing, rear bearing, both gears or crank?

 

May be best to keep it for spares and fit a new engine.

 

For the price of a few bearings i would replace the lot. I use the simply bearings 'quality budget' range on my own engines and they work fine. 

[Martin Harris - Moderator]

4 hours ago, Denis Watkins said:

Agreed

The debate is inside on YouTube

And out side in your picture Andy

Had me wondering what argument was involved until I realised you probably intended to write "rebate"!

[Denis Watkins]

14 minutes ago, Martin Harris - Moderator said:

Had me wondering what argument was involved until I realised you probably intended to write "rebate"!

I did Martin, Thank you

 

[Andy J]

Did try turning the engine over without a plug installed and it still making the clicking noise over part of the cylinder rotation so I do need to change at least one bearing. Reluctant to return the engine to the RCV dealership as I think I paid over £70 for the two shaft bearings a couple of years ago.

 

Does anyone know where I can obtain a set of cheap alternatives?

[J D 8]

               See Jon- Laser engines above post.

[Andy J]

Having just re-watched the video listed above when he installed the rotating cylinder into the bearing wondering if its worth trying to re-seat my cylinder sleeve by giving it gentle tap or two with a rubber mallet. That way the cylinder gear may sit slightly lower and avoid meshing with the crank gear.

[Martin Harris - Moderator]

Another regular/satisfied customer of Simply Bearings

[Andy J]

Thanks Martin but need to know the size and type I need to search for. Believe the main thrust bearings are 2 x 6000 deep grove types but don't know if the 6000 indicates a diameter / width. Cylinder bearing is possibly a 61806.

[Jon H]

If you strip the engine down you can either read the codes off the bearings and order more, or measure the inner/outer diameter and the thickness and put that into the simply bearings website. They then spit out all the matches. 

 

In the case of your 6000, they are 10x26x8mm and less than 3 quid. 61806 is 30x42x7 and under 6 quid. 

 

This is why i always recommend changing bearings in damaged of gummed up engines. Its just not expensive to do. 

[Andy J]

Thanks Jon. 

[Engine Doctor]

? Plus 1 for changing all bearings. 

[Manish Chandrayan]

Shaft bearings are MR6000-ZZ/C3 or 10mm X 26mm X 8mm. Remove both the seals/shields on the rear bearing and the rear on the front. You will also need bearing retaining compound to seat the bearing in the case.  

Cylinder bearing is 61806 

Last year during the lockdown, I overhauled my 58 that was put way and neglected after a test run almost a decade back.  All bearings were changed and I had the same gear mesh noise and was quite worried but in the end the engine ran perfect. Cold it still makes that noise but runs sweet 

[Andy J]

Thanks Manish. Did try re-seating the cylinder gear by giving it a few taps with a rubber mallet but continue to hear meshing of the gears over a 1/4 of the revolution. Stripped the engine again and found some rust was evident on the cylinder bearing so will change that but unclear how you get it out. Circ-clip that holds it in came out easily but cant shift the bearing.

[J D 8]

 Usual way is to warm the casing [ in the oven is one way ] then grab with a thick glove and whack it down on a block of wood.

[Andy J]

Trouble is JD that I believe the bearing is sitting on a shoulder which is larger than the bearing so its impossible to get anything above the bearing to press it down. Have tried warming up the casting with a paint stripper but could not budge it.