valve guides

How hard is it to get old guides out, new ones in and can you get a reamer (borrow one) without having to buy it? Seems like a waste for just 8 guides.

Also where can you get iron guides and are they better than bronze? Any pitfalls using iron guides?

I searched the archives and didn't see answers to these.

Thanks.

Buy or make a driver and pound them out. Grease the hole and the guide and they will follow the bore perfectly. Its not hard. Place the head on a level surface with support when driving in and out. Exhaust will be tighter on the way out. Dont worry be happy, and just do it. Ive done many heads and have not any problems. The silicon bronze guides made these days are damn tuff and id use them. I bought some for 55$ but cant remember where. Ape has them for 80 or so but they have them set up .0005 small so theyre a btch to ream and hone. They are somewhat paranoid that someone will come along and say hey why is there a hole in the center of your guides? I wanted to make that hole. So they leave it a little small and go hide in the corner hoping it will be good enough.

Be sure that you blast all of the carbon off of the nose of the exhaust guides. If you don't, it will gouge up the guide hole in the head as you drive them out.

You should have a driver with a pilot on it to drive the guides out. If they are oem 900 guides (brass, check with a magnet), drive them out cold. If they are iron 1000 type, heat the head to drive them out.

To install new guides, we have a fixture that holds the head at the correct angel in the press, and we press them in cold using assembly lube. Our guides have a machined ring on them that sets their location in the head.

Pressing the guides in will cause them to tighten up a small amount. We use a Sunnen valve guide hone to open them and size them exactly to the Serdi pilot we will be using for the valve job. Easy to do, but the Sunnen hone is expensive. We sell guide hones that the home shop can use to size guides;
www.aperaceparts.com/tools.html

Good luck.

Jay

Post edited by: APE Jay, at: 2006/05/15 02:48

Thanks for the answers guys.

Apejay, you're saying that the guides you sell don't need the circlips to locate the depth of the guide. Did I understand that correctly?

You also say you press them in, but can they safely be driven in without distorting them as nads.com suggested he did with the guides he bought?

Thanks

Post edited by: CTSZ1, at: 2006/05/15 13:45

All of our valve guides have the locating rings incorporated in the guide. You do not need the clips off of your old guides.

Never pound on a bronze guide. This can distort it and cause grief when trying to get the valve to fit.

Jay

When driving a guide be sure the driver is the same diameter as the guide, this will put a halt on the distortion. Lubing the guide alone, the lube is sheared off upon entry. Lubing the hole allows the pressure to drop under that which distorts the guide to the effect that honing is a task. With a nice little tool like apes, why it'd be a snap indeed. Coffee time.

Ape giudes are .0005 under, so after intall your looking at .001 under. If you try to ream them after this pack a lunch. They must be reamed prior to install then again after. Thats the key to the ordeal. If u dont ream them once first, youll have a hell of a time getting the reamer into the guides.

APE guides should be a bear to ream due to the high wear resistant material we use. This is the tool that should be used to size our valve guides.


Jay

Gee whiz Jay, does that tool come with the tractor to run it? Looks like a posthole digger.:laugh:

Thanks for the info guys but it looks like I'm getting somewhat conflicting info. Is the reason that Nads recommends a ream/hone prior to and after installation because of more distortion from driving in versus pressing? Seems like proper lube and correct diameter driver would minimize distortion, but pressing would certainly be less traumatic to the guide than driving.

I want to be able to get them in and have them fit properly but I am without a press and so driving would be easier but I don't want to screw them up. Would the (GH-700 7MM) hone that APE sells do the job if they were driven in? One more time please guys and thanks for your time.

Post edited by: CTSZ1, at: 2006/05/16 08:26

Post edited by: CTSZ1, at: 2006/05/16 08:30

That is a very small little hone that runs in a drill motor. As for pounding the guides in, don't know anyone that still does that. Bronze is softer than steel so it can be damaged (deformed) by pounding on it.

Most everyone uses a press and guide hone when doing heads these days. The modern Serdi type tooling requires a round and straight hole at an exact size.

If you deform the guide pounding it in, don't think the little hone we sell would be able to fix it.

How are you going to do your valve job after changing the guides? If you are going to send it out, let them worry about sizing the guides.

Jay

Thanks again jay.

I paln on doing the valve work myself. The seats don't have major pitting so I was going to use the suction stick method.

I try to do all my own wrenching and have done so for years on my automobiles, including rebuilding a '66 289 engine in a Mustang (didn't need valve guides replaced), but I still have a little learning to do on bikes.

Thanks again

If you replace the valve guides, you will have to machine the seats. You will not be able to simply lap the valves in.

Jay

Post edited by: APE Jay, at: 2006/05/16 16:43