Date: Fri, 9 Jun 2000 04:19:29 -0700
Reply-To: Mark Rokus <marokus@VOYAGER.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Mark Rokus <marokus@VOYAGER.NET>
Subject: Re: Pitted Heads
Content-Type: multipart/alternative;
HI folks
Part II: The head repair saga, according to Mark.
I have outline my experience while repairing pitted heads. Now its time to expand for those that wish to go further.
If repairing your heads is in the works for you, then you might want to consider going further and check/freshen the rest of the engine. If you were lucky enough to get the heads off without pulling the cylinders off of the pistons then you can stop here, but if you dropped a ring our of the cylinder of you want to get into the case, you will need to master the next stage of Waterboxer Mastery.
If your only problem is that you want to get the cylinder back onto the piston after a "pull-off" then it is possible to do without removing the piston from the connecting rod. Realize that this is not the method taught in the factory schools and there is a chance for difficulties, but in the tradition of Mr.. Muir, it can be done. When attempting to get a piston into a cylinder, the biggest impediment is those darned rings. They have a distinct affinity to maintain a larger diameter than the hole that you are trying to get them into. There exists numerous specialized tools for coaxing these little buggers into the hole. There are solid steel funnels that the V8 guys use that are practically useless for us. There are pliers that connect to spring steel bands that are sometimes useful if you can get access, and, when faced with getting them in while the pistons are still mounted in a Waterboxer, you can use a hose clamp. I have a couple of screw type hoseclamps that I use for this. First, they obviously have to be sized to fit the piston. Secondly, you need to make sure that they wont damage the pistons or the rings. To do that, I inspect the strap end that is connected under the screw assembly. If that end is bent so that it will scrape against the piston, I straighten it a little so that it will not dig in when it slides down the piston. I liberally oil the rings and apply the clamp over all three rings. Tighten only enough to compress the rings flush with the piston. It should hold them in sufficiently without being tight on piston. Also, be sure to align the screw so that you have access through the hole in the front of the water jacket to get a screwdriver on it. Look at what you are doing and realize that you will probably have to do the flywheel end before the pulley end piston gets in the way. It will take a long screwdriver. With the rings compressed, slide the cylinder over the piston until you come up against the clamp/rings. BTW, now is the time to make sure that you have installed the base gasket before you go further. I use a soft coaxing device (a small chunk of 2x4) to gently tap the cylinder over the piston. Be sure to constantly check that a ring hasn't fallen out from beneath the clamp and gotten underneath the base of the cylinder. If it does, you have to find a way to stick it back in or start over. There is a taper on the bottom of the cylinder and will allow the rings to go in if you don't get too aggressive. The 3 piece oil ring on the bottom of the piston is the one that usually falls out from the clamp and is a bear to get in. Keeping constant pressure on the cylinder once you start is usually the solution. Realize that the piston will rock sideways a little when you start and you can use this to your advantage by catching one side of the ring and then the other. Once you get the rings into the cylinder, you can completely unscrew the clamp and stretch the band out from around the cylinder. Patience is a must, but it can be done.
If you must get into the case, you will have to remove the pistons. Because they are inside the water jacket, conventional methods do not work well (a socket extention and a hammer). First problem is that access to the wristpin clips is limited. I have a pair of pliers for circlips that has a 90 degree bend on the tip and it allows for access from the side. I don't know of any other way without the pliers. Bend yours or get the right ones, I guess. If you can get the proper tool, then you can pull the pins out through the waterjacket holes and continue after the clips have been removed. If you don't have the tool then you will have to improvise. I crafted a tool from a long bolt and some pipe. The requirements for the tool are as follows: The bolt is actually threaded rod sized to fit into the bore of the wrist pin and be about three times the piston diameter in length. The pipe bore has to be bigger than the outer diameter of the wristpin and the outside of the pipe has to be smaller than the hole in the waterjacket that lines up with the pin. This is because the pipe will be pushing against the piston while reaching through the waterjacket. Length is about the same as a wristpin. Copper pipe might work nicely but mine is steel so I made sure the edges are smooth and fit evenly against the piston. A cap with a hole or a washer is used on the outer end and a nut that has been gound down to fit through the piston (wristpin) is used on the other end. The procedure is something like this: First, you remove the circlips on both sides of the piston. Secondly, try and clean the varnish our of the wristpin bore with carb cleaner or mechanically. Third, insert the threaded rod through the waterjacket hole and through the wristpin. Fourth: thread your ground down nut onto the screw as a way to grab the wristpin from behind. Fifth: insert the pipe through the waterjacket hole and over the threaded shaft. What you will be doing is pulling the pin into the pipe and out of the piston. Sixth: install the cap or washer so that it will pull the shaft through the pipe. Add a normal nut to the stack and turn so that it pulls put the pin into the pipe and out of the piston. Be careful that the pipe is centered on the hole so that the pin doesn't catch on the edge of the pipe when it starts to come out of the piston.
I realize that its hard to visualize this without a picture. If need be, I'll come up with something for those that need it. It should become obvious after a while, if you first try and draw on paper what I have tried to describe.
I hope this allows a few more Vanagons to stay on the road.
Mark Rokus
-----Original Message-----
From: gerry rafferty <gerryr@direct.ca>
To: Mark Rokus <marokus@voyager.net
Date: Wednesday, June 07, 2000 4:32 PM
Subject: Re: Pitted Heads
Mark
Great article.I'm going to take the heads to a shop to check valves/guides/cracks.
Now trying to remove the pistons to split the case-snap rings are being a pain to remove.Any suggestions welcomed.I don't have a wrist pin removal tool-do I need to get one?
Thanks
Gerry
----- Original Message -----
From: Mark Rokus
To: gerry rafferty ; vanagon@GERRY.VANAGON.COM
Sent: Wednesday, June 07, 2000 3:20 AM
Subject: Re: Pitted Heads
I have written my story in the past, but I never took the time to elaborate.
Here is my experience.
An Alternate Method to Costly Head Repair on Leaking Vanagon Heads.........
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