Wednesday, April 8, 2009

Off with my Head. Part 3.

Good news
The machine shop called - the cylinder head passed the pressure test!


Bad news
The machine shop called again - the cylinder head failed the pressure test!

The real news
While the head passed, the valves were not holding pressure. Not a big deal since a valve job would tighten this up. On to the valve job!

The really bad news
When polishing the head for the valve job the shop found cracks in the exhaust ports for cylinders 2 and 3. At least one of the cracks extends outside of the valve seat area into the head.
You can't really see the cracks in this pictures so I marked the locations on the head with a marker.So why didn't this show up in the pressure test? The cracks may open up when the head is hot, or the leak may have been solely from a failed gasket. Regardless, I need to find a replacement cylinder head. I'm working a couple of leads but this may take a while. The late heads have a greater tendency to crack.

I removed the remaining studs from the block. If you break one off you have to pull the lump and take the engine to a machine shop. Removing 4 stuck studs took 2 hours of gentle heat, persuasion and patience.

The quest for a replacement head begins...

Thursday, March 26, 2009

Off with my Head! Part 2

What lurks beneath

With the head off its time to examine the cylinders, block and pistons. Lets start from the back and work forward. Cylinder four has a carbon buildup but looks okay.

Cylinders 2,3 are similar to 4.And now for something rather different! Cylinder 1 has carbon but has a light grey appearance. This may indicate a gasket failure resutling in coolant "steam cleaning" the top of the piston.
The location indicated by the green arrow was full of "grit" that reminded me of a hard water scale or buildup. More evidence of a failed gasket.

Here are the valves. These look okay but only a pressure test will tell definitively.
Now its off to the machine shop for pressure testing, magnafluxing and a valve job, assuming all goes well and no cracks are found in the head. Could it be that easy?

More info
This site has some excellent information about MGB head identification, etc:
http://flowspeed.com/cylinder-ident.htm

Off with my Head! Part 1

It started out innocently enough...
Doesn't it always? When I took the car off the road in November 2006 the cylinder head had developed a slow weep between cylinders 2 and 3, just above the engine block number plate. In this picture you can see the greenish coolant where the head meets the block. Trust me, its there - just above the engine number plate, below spark plug number 2. You see it. I know you do.


No problem - whip off the head, change the gasket and we're good to go, right? Not so fast. Late model heads are prone to cracking in this region. Max Fulton at Flying Circus English Cars also told me that late model blocks can sag in this area, or the block can pull up around the studs. So what could it be? Its an old British car - how could it be anything but a simple gasket failure?

I drained the cooling system, unhooked the hoses and took off the valve cover and rockers. Here we are after backing off the head nuts in a spiral pattern as described in the shop manual. Check out the stud with the nut still on. It unscrewed easily directly from the block. Interesting....

When pulling the pushrods angle them to the side so the tappets will stay aligned. Its important to remember the order so I pushed them through a box and labeled each. Wow - look at how professional I am.



With the pushrods out I unhooked the manifold and pulled it back away from the head.


At this point you can lift the head away from the block. That is what the manual says. Reality was more complicated. The head was stuck to the block at the stud indicated by the green arrow. I could rock it up and down on each end but it is stuck in the middle! Blue arrow shows the location of the weepage and red arrow the stud the screwed easily out of the block.


I repeated applications of my new favourite penetrating oil (hmm, that sounds dirty) Kroil www.kanolabs.com over a period of a few days to the top of the stud and where the head meets the block. I also applied some light heat from a propane torch and some gentle tapping with a hammer on the top of the stud. After a few days it came loose! What suprises will be found underneath?

Sunday, October 19, 2008

New Struts for the GT

With major house renovations underway I dont have much time for the MG's. Tonight was a brief respite from drywall and flooring. I spent a few minutes swapping out the original mechanical hatch lifts with gas struts from Rick Ingram of Pieces of Eight. This is a quick and easy upgrade that anyone can do in a few minutes. Rick provides good instructions (though the pictures could be a bit bigger). Below are a few supplemental pictures for the process.

The old lifts were a mess. One had a bolt missing that allowed the lever to slip out and have the hatch come crashing down on my head. This was not even comical the first time it happened. It was time to bring the lift system into the next century.This is the connection at the hatch where I had to drill out the bolt that faced inward. It was crimped and there was no good way to get any purchase on it. The bolt was removed from the connection to the car body and the two washers reused with the new ball connector.
When fastening the ball to the attachment point on the body, move the ball as far forward toward the front of the car as possible.
With the ball in place for the body you can use the strut to guage distance, but more importantly use Rick's instructions that state the new attachment point should be 12 inches from the original point (measuring down toward the bottom of the hatch). See two pics down for the measure point. Use the new bracket to mark the attachment point and drill two 3mm holes (yes I know I mixing metric and imperial here...). Attach with the screws provided. Repeat for the other side.

Ta-da! Now enjoy the gas-strut action as you raise and lower the hatch. Place your head under the raised hatch and notice how it no longer falls onto your cranium unexpectedly! Right nice.

Now unfortunately its back to drywall, painting, and laying a hardwood floor over the next few weeks. Hopefully I'll be back to the MG's soon...

Sunday, August 17, 2008

NCMGCC 20th Anniversary Meeting

I joined the North Carolina MG Car Club a couple of weeks ago, just in time to attend their 20th anniversary meeting. The meeting was held less than a mile from our new home. On the way into the parking lot I could already tell there was a great deal of talent here....
Nice cars and even nicer people. I can't wait to get my cars back on the road after seeing so many great cars in such an active and inviting club.

Saturday, August 9, 2008

2 MG's, One Truck: the move to Raleigh, NC.

I've missed updating the blog for several months because I changed jobs and moved 250 miles south from Charlottesville, Virginia to Raleigh, North Carolina. Prior to the move I welded in the dogleg and front wing replacement panels. I may get back to documenting that later. But first, how to move 2 MG's the 250 miles? Why simply back up the MG X Power Transport and load 'em up!
Reality was more complicated. I looked at several options. The GT has no brakes and may not be considered a "runner," in which case it would cost the value of the car to move it. The cost of hiring a transport for two cars was substantial and I needed delivery flexibility because we had not yet closed on our new house.

The MG Shocker: One in the truck, one on the trailer.
I decided to rent a truck and place one in the box of the truck and one on a trailer behind. I had hoped to take several pictures but did not for two reasons: 1) I was too busy the day of the move 2) I don't want you kids trying this at home, then suing me when something goes horribly wrong.

I rented a 17' truck (van) from a local moving company. Its the southern USA, so I'll just call it "Y'all Haul" because I don't want to name names. I took a "don't ask, don't tell" policy with the rental and purchased full insurance on the truck. The plan was to put the LE in the box since the 17 footer has a box just over 14' in length - plenty of room for the LE with space to walk beside the car. With the car pulled up all the way to the front you have almost a foot to spare at the back. But how to get it in there?

My original plan was to back up the truck to the slope in our lawn and load the car in using ramps constructed from doubled-up 2"x12" plank, braced with concrete block (a bit dangerous, obviously). I purchased some ramp tops from Lowes and had them ready with my 2"x12"s.Now don't get any silly ideas - I'm not suggesting anything like this:
The movers noticed what I was doing and offered the use of their loading ramps which turned out to be ideal for the job. One ramp was placed on either side and I drove the LE up and into the box of the truck from street level. The LE is lowered but there was just enough clearance. This is the part where I really wish I had some photos. Driving the MG up and into the box was like taking a ride at an amusement park. Once the car was in I blocked the wheels, secured the car in place and disconnected the battery.

The GT turned out to the be most difficult. Since I rescued it from the impound lot it has always started without a problem. Not the day of the move! Fortunately I was prepared and had purchased a "come along" hand winch from Harbor Freight. This allowed me to pull the GT up onto the trailer all by myself. Later I used it to slowly back the GT off the trailer. Very useful and only $17 at the local store.

Here is the moving truck leaving our place in Virginia. Note the LE in the moving van and the GT loaded on the trailer. All that was left was to hook up and trailer and we were off. We left around 10:30pm and pulled into Raleigh around 2:30am with no troubles.

A couple of days later I offloaded both cars. I was able to back the GT off the trailer using the hand winch, then unhook the trailer and back up the truck into the ditch in our yard. This brought the deck of the truck almost level with the lawn. I constructed two six foot ramps using my 2"x12"s, braced them well with concrete blocks, and backed the LE off the truck with ease. Home at last.

Sunday, March 2, 2008

Back to the LE - Sill Work

It's been a while since I've done much work on the MG's. One of our Great Danes took ill in mid November and our other one passed away at age 10 and a half only 5 days before Christmas. We still don't have a diagnosis for our boy, who turned 6 years old in February. So my heart has not been into the cars as of late.

I have been doing a little work as time and finances allow. I decided to turn my attention back to the sill work on the LE in the hopes of having it back on the road this summer. I will finish the drivers side and leave the passenger side for later.

It was a year ago when I had attached the castle rail and work stalled at that point. The outer rocker is shown on the floor. The inner membrane is first welded into the castle rail, then the rocker.
A pneumatic hole puncher was a great help in prepping the inner membrane for the welds to the castle rail. Holes for welding were punched approximately every inch, then the section was welded to the castle rail (not shown)
Adjusting the rocker took a long time. This is where you start to see how well (or badly) you have lined things up. Getting the gaps correct around the door is critical. If you mess this up you might as well quit right there. So I took my time and found that things are a little off at the front but overall are ok. For a first timer I am happy with the fit. The front wing is on temporarily to assist with fitment only. It was then removed and the rocker plug welded into place.

Next up - the dog leg repair behind the door.