Hot Rods How Difficult & Expensive to Replace Valve Guides at Home? Do a Valve Job?

I chucked up one of the galled valves in a drill and used 400 grit paper. I managed to polish the galling and grooves out. Need to mic it to see how much material I lost, but I think this is a viable route. EDIT: Looks like I took off about .001" of OD.

As for enlarging the guides to the correct size, they're currently at .3885" or so, depending on the guide. I'd like to get them to .3895" or so on the intake (.0025" clearance) and about .3900" on the exhaust (.0030" clearance).

Would I do this with a reamer or with a hone? Reamer makes me a bit nervous about having it perfectly centered.

Thanks

 

Guides are best handled by a shop. Positive seals can be done at home with the purchase of the proper tool and pretty easy to do if you know valve lift. Remember to lap the valves in before installing the seals.

 

Keep an eye out for a seat and guide machine, they pop up here every now and then for decent price.

 

How does someone learn anything if they pay someone else to do it ? Taking your stuff to a shop is no guarantee it will done correctly. This place is amazing.

 

exactly true......good valve work is a precision job.. getting the guide concentric with the valve to aviod excessive seat grinding that kills performance...You can do it at home, all depends on what you consider acceptable....

 

I would use a reamer. They are piloted. I think it would be likely to get more out of kinder with a hone. You'll be doing a valve job either way. Mike

 

My point exactly!!! Thanks for the comment!

 

Mike - thanks. I figured I would be doing a valve job, too, but why is that? Because even the slightest deviation in the angle of the guide will throw off the valve job? Thanks

 

Yes, both angle and concentricity of the new guide. A little ink/blue on the seat and spin the valve, will tell you how much. Mike

 

I can imagine them saying, Due to insurance regulations, we cannot allow customers in the shop. I mean, would you want people starring at YOU while you work?

 

I just read through this kinda quickly but it looks like you only need to take a couple thou out. As mentioned the reamer is the better choice. A small flex hone will never get you there and the ridged valve guide hone setup is really expensive. And as also mentioned valve guid reams are piloted to keep you straight. Going back to the bronze guid liners. The Goodson setup looks like it changed. I have to older system and the cutter it uses is piloted and using it on a guid that’s already.015 over gets tricky as there’s a lot of slop for the pilot to manage. The newer system may work better but wanted to throw it out there.

 

I seem to remember there being a process of repairing worn valve guides that involved a process similar to installing thread repair inserts. The guide is drilled out with the proper size bit, then it is treaded with the tap provided in the kit and bronze wire insert is threaded into the guide and then reamed to size. This was decades ago and my memory is fuzzy, I never did the job myself and have no firsthand experience with it, but I do recall hearing and reading of this being done. One of those innovative repairs that people did when they didn't have the time or money to do the job correctly. It worked for a temporary repair.

 

Valve job requires a valve grind machine to cut the seats.
As for guides, we have been doing bronze guides for years with hand tools. You do not remove the old guide, you drill it out pass a knurl through it and install a bronze sleeve in it. Pretty common performance mod.

You can get a kit from your favorite automotive catalog speed shop. I prefer a place in ohio but you can choose whatever one floats your boat.

 

I've never built a motor (+10) that I didn't have the machine shop install bronze guides.

I one of those people that when it comes to building an engine that I plan on driving it a long time and totally hassle free. I hate putting good money into something just to have to take it apart several yrs latter.

..

 

Ok, the reamers that I'm looking at (someone posted a link earlier) are "Piloted for self-centering action." The only issue is the size. I was hoping for .389", but they have .388" and .390". The .390" should be perfect for the exhaust (leaving me with .003" clearance) but I didn't want to go to .003" on the intake. Anyway, I think I'll order the 3.90" and use it on the exhaust guides. On the intake I may just be able to hit them with a hone and call it good. BTW - the heads came off a turbo engine and it's getting a turbo again, but with a bit more fuel and about the same boost. That's why I want to make sure the guides aren't tight again on the exhaust.

Thanks

 

Yeah the Sunnen valve guide hone setup is about $2,000 new. Budget can't handle that right now.

 

Valve jobs can be done at home without a specialized valve grind machine. I'm not there yet, but that will be my next step.

Thanks

 

In the past, I have been a bit of a perfectionist when it comes to building motors. I'm trying to get away from that and at the same time, I'm trying to do more of the work myself. If that results in me pulling an engine to fix something that was jacked up, I have no one to blame but myself. I'm ok with that.

 

Neway valve seat cutters. I think if you search around may find tooling for guide work. Since mine were press in stock I replaced with bronze and reamed to size with couple adjustable reamers.

http://www.newaymfg.com/

https://cheaper99.com/neway valve s...cutters&utm_content=adgroup [24|w4|b]: {5-ne}

 

Yeah, that's the next purchase, I think. With the $800 I saved from not buying the bronze liner installation kit, I can pick up a valve seat cutter setup.

Thanks

 

I ordered the .390" piloted reamer.

Need to order a valve guide hone; the 3/8" will be too small since I'm at 3/8" + .015" on the guides. Next size up is 10mm. That should work.

 

You know what your next purchase will be right? A head resurface machine, well, 2nd in line after you get a precision straight edge.
I admire your DIY attitude, I can still do a lot of things, but now take a lot of things into shops that do it daily.

 

Already have the straight edge; check out the video link I posted above to see it in action!

I may end up using a "redneck resurface machine" -- sandpaper glued to some thick plate glass. One of my cylinder heads has just shy of .002" warp; still within spec, but I'd feel better if it was less than .001"...

 

Got a few silicon carbide flex hones ordered in 10mm/.394" - one in 120 grit for intake guides that are a bit tight (I do realize that this is not likely to remove much material), and then 240 grit for a finish hone on all guides. Other option was 320 grit for finish hone but apparently diesel engines like a slightly coarser surface to better retain oil.

 

I copyed these stands to use on a Bridgeport but they will not work on canted valve heads. https://www.bing.com/images/search?...ide+machine&ajaxhist=0&ajaxserp=0&vt=0&sim=11

 

Of course most of us love to learn something by doing it ourselves. But the lesson learned shouldn't be what to do to ruin parts, and waste time and money. If I had a junk head and plenty of time to play with it, I still wouldn't try to hand ream or fit guides to it. If the head had press in guides already I'd consider playing around with pressing in a new guide just to see if I could. But I certainly don't want to learn what not to do if it results in screwing up a pair of heads that could have been repaired correctly.

 

I've cleaned up the mating surface on heads using a large aluminum block wrapped with emery paper and some WD40 or kerosene to wet sand the surface. But the heads were true and straight before I started, so I wasn't truing the surface, just making it very smooth before installing new head gaskets.

 

Right, man's gotta know his limitations

 

Good point on glass tables. Will have to figure out what grit sandpaper to use and where to source a large enough sheet of it.

The website for the flex hones was actually quite informative. That's why I chose the size that I did.

I actually ordered a quart of honing fluid because it wasn't that expensive. I'll use it when I use a ball hone on my cylinders as well.

Thanks

 

As mentioned earlier, I prefer to do things myself and I enjoy the learning process. Yes, it's more challenging and time-consuming (and sometimes more expensive), but it's a lot more fun - at least for me - than writing a check.