Topic: Just like that, it all came to a halt...

[GardenGnome]

Was doing some removal of valves this evening and when i pulled the rubber bit i noticed a crack around the valve guide (not sure if that's accurate terminology). So I took the tip of my knife and lightly poked at it, it didn't take much and this is the result. I'm no expert, but I'd assume that I'm pretty well screwed at using this engine. Which really is a bummer because I was hoping to keep the original motor with the frame. That's not what I expected, but it's a drag I have to go looking for another motor.

[madmtnmotors]

Valve guides are replaceable.

[innovativems]

Pull the head and send it to Jmr porting.  Mreick is the man on here!


Sent from my iPhone using Tapatalk

[GardenGnome]

Hmm, you don't say. Any sort of info on how to replace? or is that a job better left to a professional like what user innovativems suggested?

[Jimray23]

Leave it to a pro

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Jim
I really don't see why people ask for advice if their not going to take the advice given.

[GardenGnome]

Leave it to a pro

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Jim
I really don't see why people ask for advice if their not going to take the advice given.

Duely noted. I'll have to see if any of the shops around here could handle that.

[Jimray23]

Any decent engine shop should be able to do it.

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Jim
I really don't see why people ask for advice if their not going to take the advice given.

[GardenGnome]

Quick edit. I was wondering why this had happened, turns out the valve that was in the place of the broken valve guide has a nice slight little bend to it, not that noticeable, but in all honesty the valve itself was a little bit of a, *clears throat* pain in the butt to remove. Now I get it, cause and effect. I'm just glad that I can still reused this part of the motor, that really makes me happy.

[GardenGnome]

Any decent engine shop should be able to do it.

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Jim
I really don't see why people ask for advice if their not going to take the advice given.

I'll ask around, I know there's some out here. Just out of curiosity though, how come you don't recommend I do it myself?  Is there a particular degree the guide has to sit at? If I bought the part and brought it to the machine shop I would assume that would be acceptable and hopefully cheaper than having them buy it...I just don't know enough about what this all entails now. I was trying to avoid having to send the engine anywhere and rather have myself do all the work, but if this instance needs the touch of a professional then by all means I'm for it.

[Jimray23]

It has to be lined up just right and made yo fit the valve with the  correct clearances. And I've heard stories of people pushing them through the head. You will probably have to order the guide or guides.

Edit: and the valves

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Jim
I really don't see why people ask for advice if their not going to take the advice given.

[Jimray23]

Quick edit. I was wondering why this had happened, turns out the valve that was in the place of the broken valve guide has a nice slight little bend to it, not that noticeable, but in all honesty the valve itself was a little bit of a, *clears throat* pain in the butt to remove. Now I get it, cause and effect. I'm just glad that I can still reused this part of the motor, that really makes me happy.

I would say you got lucky. You might want to have the machine shop check for cracks while your at it

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Jim
I really don't see why people ask for advice if their not going to take the advice given.

[GardenGnome]

Quick edit. I was wondering why this had happened, turns out the valve that was in the place of the broken valve guide has a nice slight little bend to it, not that noticeable, but in all honesty the valve itself was a little bit of a, *clears throat* pain in the butt to remove. Now I get it, cause and effect. I'm just glad that I can still reused this part of the motor, that really makes me happy.

I would say you got lucky. You might want to have the machine shop check for cracks while your at it

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Jim
I really don't see why people ask for advice if their not going to take the advice given.

Good call . I'll see what I come up with. Texting friends now who might be able to point me in the right direction of a good shop. Thanks to you guys too, if nothing psbs out locally I'll see about getting a hold of the guy  innovatiems suggested.

[TwoTired]

Turns out, I'm doing a valve guide replacement on my CB 550.

Head has to come off and be cleaned.

The head has to be heated so it will expand.  The guides are an interference fit into the bore of the head.
The guide is then driven out while the head is hot and expanded.  There is a driver tool for this.
The new guide is an interference fit, too.  Again heat the head and also freeze the guide to shrink it.
Drive the new guide into place with the driver.
Reheat the head for the next guide.
Now the new guide is reamed for proper clearance to the valve stem being used.
The valve seats now need to be re-cut. A three angle will do but a five angle is better. If doing just one , it should match the others.
The valve is then lapped for optimum seal.
The head is then reassembled and installed on the engine.

Simple, eh?

[BomberMann650]

Turns out, I'm doing a valve guide replacement on my CB 550.

Head has to come off and be cleaned.

The head has to be heated so it will expand.  The guides are an interference fit into the bore of the head.
The guide is then driven out while the head is hot and expanded.  There is a driver tool for this.
The new guide is an interference fit, too.  Again heat the head and also freeze the guide to shrink it.
Drive the new guide into place with the driver.
Reheat the head for the next guide.
Now the new guide is reamed for proper clearance to the valve stem being used.
The valve seats now need to be re-cut. A three angle will do but a five angle is better. If doing just one , it should match the others.
The valve is then lapped for optimum seal.
The head is then reassembled and installed on the engine.

Simple, eh?

They say if you can explain a complex process simply, you are a master of it.

[754]

Way easier sounding than when Soy Boy explains it..

[camelman]

Definitely a doable job. Might want to check all of your valves. The ends can mushroom if the rocker arm clearances get too large, and then scratch the inside of the valve guides upon removal or reassembly. Might have been what happened when you removed the valve from that guide, although with more dramatic results.

You can dress any mushrooming down with emory cloth. Just make sure to clean any residue off so that you don't scratch the guides.

I'm a fan of learning by doing, so I encourage you to do it! Good luck!

Camelman

[GardenGnome]

Turns out, I'm doing a valve guide replacement on my CB 550.

Head has to come off and be cleaned.

The head has to be heated so it will expand.  The guides are an interference fit into the bore of the head.
The guide is then driven out while the head is hot and expanded.  There is a driver tool for this.
The new guide is an interference fit, too.  Again heat the head and also freeze the guide to shrink it.
Drive the new guide into place with the driver.
Reheat the head for the next guide.
Now the new guide is reamed for proper clearance to the valve stem being used.
The valve seats now need to be re-cut. A three angle will do but a five angle is better. If doing just one , it should match the others.
The valve is then lapped for optimum seal.
The head is then reassembled and installed on the engine.

Simple, eh?

Ha, I appreciate the simple breakdown of how the process is achieved. That being said, I do believe I will seek out a professional doing the task  . Not that I'm lazy, just not ready for tackling this.

Question: since I have to replace the one valve guide, does it make sense to replace them all? Or should I just do the one(s) that need it? Follow up question, I read a thread about another member doing the same thing with valve guides. The thread stated that trying to find the OEM exhaust valve guide is a difficult. On 4into1 they sell the intake valve guide, however on the dynoman website it states that both the intake and exhaust valve guide are the same. Is this true for the OEM Honda ones from the 4into1?

[scottly]

Quick edit. I was wondering why this had happened, turns out the valve that was in the place of the broken valve guide has a nice slight little bend to it, not that noticeable, but in all honesty the valve itself was a little bit of a, *clears throat* pain in the butt to remove. Now I get it, cause and effect. I'm just glad that I can still reused this part of the motor, that really makes me happy.

Bent valves and guide damage on 550s are due to improperly installing the cam-cover; the tappet adjuster screws aren't centered over the tips of the valve stems, and the valves get bent as the cover is tightened down. One method to avoid this is to use rubber bands to hold the rocker ends up when the cover is installed.

[GardenGnome]

Quick edit. I was wondering why this had happened, turns out the valve that was in the place of the broken valve guide has a nice slight little bend to it, not that noticeable, but in all honesty the valve itself was a little bit of a, *clears throat* pain in the butt to remove. Now I get it, cause and effect. I'm just glad that I can still reused this part of the motor, that really makes me happy.

Bent valves and guide damage on 550s are due to improperly installing the cam-cover; the tappet adjuster screws aren't centered over the tips of the valve stems, and the valves get bent as the cover is tightened down. One method to avoid this is to use rubber bands to hold the rocker ends up when the cover is installed.

That's great to know. I'm not sure if this engine ever had any service done to it prior to me buying it, but it certainly seems like it didn't, I say that because of all the carbon build up. Of course to be honest, I'm not sure how long it would take for carbon to build up the way it did/is on my bike. I'm sure there's many factors that play into that.

[scottly]

http://forums.sohc4.net/index.php?topic=82508.0

[GardenGnome]

http://forums.sohc4.net/index.php?topic=82508.0

Whatever the equivalent to buying you a beer is for the internet, that's what I want to do for you sir! Did that come off as weird, I feel like that came off as weird...although sincere.

[scottly]

Cyber beer accepted.

[TwoTired]

Turns out, I'm doing a valve guide replacement on my CB 550.

Head has to come off and be cleaned.

The head has to be heated so it will expand.  The guides are an interference fit into the bore of the head.
The guide is then driven out while the head is hot and expanded.  There is a driver tool for this.
The new guide is an interference fit, too.  Again heat the head and also freeze the guide to shrink it.
Drive the new guide into place with the driver.
Reheat the head for the next guide.
Now the new guide is reamed for proper clearance to the valve stem being used.
The valve seats now need to be re-cut. A three angle will do but a five angle is better. If doing just one , it should match the others.
The valve is then lapped for optimum seal.
The head is then reassembled and installed on the engine.

Simple, eh?

They say if you can explain a complex process simply, you are a master of it.

I'm no master.  I haven't done it yet on the 550.  But, I do research before the doing.

Cheers,

[BomberMann650]

The pre-77 550's will also muss up their valves when the rocker shafts get bored of boring in their factory bored bore.

Its all part of honda's self-destructing conspiracy

[GardenGnome]

I rally want to tackle this myself, just all the cutting of balves boring them, honing them, and even the process of uninstalling and installing just seems a bit much. Ive got a feeling the local guy who works on these old Hondas is going to tell me it's going to have to wait until winter. It's that or bring it to a major city and find someone to do it.