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Rebuilt engine seized

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GregMcN
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Posts: 236
Joined: Tue Jul 04, 2017 3:34 pm
Location: Richmond, North Yorkshire, UK

Post by GregMcN » Sat May 19, 2018 4:16 pm

I think I have managed to work out how to post from image hosting site, so here are pictures of the top end. I think there is some wear on the inlet lobes but nothing new and no real difference right to left

Image

Image

Unfortunately I have now dismantled the oil pump and that appears to be damaged, wear particularly on top cog and scoring of pump body. I did strip on the original rebuild and did not notice anything so my assumption is this is as a result of the seizure rather than cause.

Image

Image

Greg

honda brian
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Location: Ballarat Australia

Post by honda brian » Sun May 20, 2018 1:28 am

Nice Greg. Just to satisfy my curiosity, can you pull out the rockers and post some pics of the sliding faces? I do think it's starting to point towards a roller cage breakup though. Which in the scheme of things is good because the top end will have had some oil. Shame about the pump. I would have thought that the screen would have stopped most of the junk going through the pump. Luckily, pumps are easily available.
Onward and upward mate.
Brian.

GregMcN
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Posts: 236
Joined: Tue Jul 04, 2017 3:34 pm
Location: Richmond, North Yorkshire, UK

Post by GregMcN » Sun May 20, 2018 3:39 pm

Hi Brian

It's confession time, it is looking as if I messed up. When I checked back to the original rebuild pictures it looks as if the groove in the pump casing was already there and I did not notice it. I measured the tip and meshing clearances which were (and still are) well within spec. The screen looks OK. How the pump got damaged I have no idea but would be before my ownership.

I think the pump was still moving oil because I had leakage problems initially at the base gasket when the metal tube was in place and then I did have to tighten down the tappet covers so there was oil getting to the top but maybe not enough to the RHS bearing?

I have not stripped the top end so far so will have a think about that.
Yes onward and upward
Greg

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G-Man
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Post by G-Man » Mon May 21, 2018 3:00 am

Greg

Glad you got the picture thing sorted.

I have a variety of pump pieces that will get you going with a decent pump. Please bring your old pump housing along as a couble of years ago, I developed a technique to rescue them and increase the capacity, by re-machining the housing to fit bigger gears.

It's a bit of a fiddle to do but I'm taking delivery of a new milling machine with digital readouts soon so it should be much easier.

G

Image

GregMcN wrote:I think I have managed to work out how to post from image hosting site, so here are pictures of the top end. I think there is some wear on the inlet lobes but nothing new and no real difference right to left

Image

Image

Unfortunately I have now dismantled the oil pump and that appears to be damaged, wear particularly on top cog and scoring of pump body. I did strip on the original rebuild and did not notice anything so my assumption is this is as a result of the seizure rather than cause.

Image

Image

Greg
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F

GregMcN
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Posts: 236
Joined: Tue Jul 04, 2017 3:34 pm
Location: Richmond, North Yorkshire, UK

Post by GregMcN » Mon May 21, 2018 10:10 am

Rockers

RHS inlet
Image

RHS exhaust
Image

LHS inlet
Image

LHS exhaust
Image

Hard to get good representative pictures, I think there is some more wear on the RHS side more so on the inlet but I do not have the experience to judge acceptability.
The RHS exhaust rocker has a hole in the face rather than the body??

Greg

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G-Man
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Post by G-Man » Mon May 21, 2018 12:45 pm

RHS inlet looks rather nasty.

Rockers with holes in pads are later ones. More prone to trouble in my experience.

Graham
GregMcN wrote:Rockers

RHS inlet
Image

RHS exhaust
Image

LHS inlet
Image

LHS exhaust
Image

Hard to get good representative pictures, I think there is some more wear on the RHS side more so on the inlet but I do not have the experience to judge acceptability.
The RHS exhaust rocker has a hole in the face rather than the body??

Greg
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F

User avatar
G-Man
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Posts: 5678
Joined: Wed Mar 25, 2009 5:17 pm
Location: Derby, UK
Contact:

Post by G-Man » Mon May 21, 2018 3:03 pm

RHS inlet looks rather nasty.

Rockers with holes in pads are later ones. More prone to trouble in my experience.

Graham
GregMcN wrote:Rockers

RHS inlet
Image

RHS exhaust
Image

LHS inlet
Image

LHS exhaust
Image

Hard to get good representative pictures, I think there is some more wear on the RHS side more so on the inlet but I do not have the experience to judge acceptability.
The RHS exhaust rocker has a hole in the face rather than the body??

Greg
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F

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