<< | show individual entries | >>
January 18, 2005:
The Seven lost its head last night.
This guaranteed beautiful weather today of course. The head came off quite easily because of the amount of room around the engine with the hood and nose removed from the car. It's a radical difference from working on the same engine on my GTX - sitting right beside the Seven with its own head removed. The fairly unusual cams I'm using are showing some rapid wear. That's not reassuring. It's the first time I've actually looked at them. They're quite high lift and short duration from the looks of it. I'll bet they'd really enjoy some good springs. Naaah, maybe later. Hopefully the head can be fixed up with new valve seals fairly quickly. Then I can start working on extracting a little more power. While I'm waiting for that to return I have a number of small jobs to do on the car such as some cosmetic cleanup, ducting for the radiator and - yes, Eric - a grille.
January 19, 2005:
The machinist looked at the Seven's head last night and said "you have bad rings" immediately. So while the head is off, I'm going to pull the pistons and re-ring them. The engine has probably 5-6,000 miles on it but it did sit for loooong periods without being started. When it was started, it was usually run hard by someone who didn't own it. So that's probably where much of the damage comes from. The cams are scarred as well but the journals are good. So I'll just put them back in. At this point it'll be fairly easy to pull just the engine and leave the transmission in the car (I hope) and I can re-ring the block without too much expense or effort - but I really hadn't planned on pulling the engine again...
In contrast to the fun outdoor photos of a few days ago, here's the current state of the Seven.
My cams are showing some rapid wear.
I'll put them back in, as they're only damaging the lifters and I have more of those. I wonder if this comes from the engine sitting for long periods before I bought it?
January 20, 2005:
The engine is out.
Of course, after I ordered a fresh set of rings for an 80mm bore (as I was told I had when I bought the engine), I measured the bore and found it to be 79mm. Argh. Oh well, at least the whole engine removal went easily. One advantage to the order in which I built the car is that I had to consider how to install the engine late. The typical way to build a car like this is to put the engine in first and then build around it. That can cause problems down the road - particularly if you're like me and pull the engine twice after the car is "done".
I used to scrape the oil pan lightly when entering my garage.
The result was this customised oil drain plug!
I had hoped not to see this sight again, honestly.
The engine comes out for new rings.
January 21, 2005:
The source of the oil use has been found.
The forged pistons protrude slightly from the block. When cold, they were able to rock in the bore slightly and they'd hit the head. Once warm, they were probably okay as the engine never made any alarming noises. Regardless, this behaviour meant the oil rings were damaged. Oh well, I did get a great deal on the engine so this isn't a major problem. I'll check to make sure the pistons are okay. If not, the engine will get bored out to 80mm and I'll put in some fresh ones. It won't be the cheapest solution but it'll give me a bit of a power bump. If the pistons are good, I'll pop them back in after being slightly cut down to prevent this from happening again. Hopefully I'll have this all back together and in the car in a couple of weeks. I have access to everything but a good set of "street" 79 mm rings at the moment.
My cool clutch - it's the first time I've seen it apart as I bought the engine with it already installed.
Dual Kevlar discs. It'll hold a ludicruous amount of torque. Not that I need it.
Pulling the clutch off revealed this problem.
It'll be fun finding a replacement fastener.
The source of my oil consumption? The pistons were hitting the head! You can't see the impact marks well in this photo.
It's hard to believe that less than I week ago I was happily driving this car.
The refresh is taking longer than expected, but it'll be a strong engine when I'm done.
January 25, 2005:
The pistons are off being modified and my new rings should be here on Friday.
I need to make a small repair to the clutch and then it's ready to go back together. The head is done and is absolutely gorgeous. Mmmm. I'll try to take some photos of that soon.
January 27, 2005:
Why did I take apart two engines at the same time? I must have some sort of problem.
The GTX is in the middle of being reassembled and I'm gathering the parts for the Seven. It's a bad habit. I'm still waiting for the last bits for the Seven's bottom end. The new steering knuckles arrived yesterday. I'm not sure if I'll install those now or wait until I can drive the car into the shop.
My new steering knuckles and tie rods have arrived.
They're from a 1999 model with a higher steering arm.
January 28, 2005:
Well, the modified pistons are here.
It's good having machinist friends. I've probably lost a tiny bit of compression but that's not a huge problem - it might only be 10.75:1 now. The rings are here as well so I'll spend the weekend reassembling the engine. First step, a coat of nice new paint so I don't feel I'm putting a grungy engine into my car!
My pistons have been cut down a bit to prevent any further interference with the head.
January 29, 2005:
The pistons are now reinstalled in the block and the head is ready to pop on. It's satisfying work doing this but it's been a while so I'm a little rusty. My friend Bill Cardell was good enough to put up with my questions, although he'll probably be surprised to see how much I accomplished once he left! The engine is currently waiting for a gasket for the oil pump pickup - we have some at Flyin' Miata, I just have to make sure I can use one - and then will go back together. Tomorrow I'll probably work on the GTX because I'd like to be able to drive it. At this rate, the Seven will be back on the road fairly soon and with a strong engine on board. Once it's broken in, I'll hit the dyno and see how much power awaits.
The head, ready to be installed.
I love working on clean, well machined parts.
The rings are ready to be installed and the head has the cams in place.
Installing the pistons.
I had considered changing these Carrillo H beam rods for A beams due to the lighter weight, but decided to keep them. The red goo is Redline assembly lubricant.
The advantage of working at Flyin' Miata - access to tools like this digital Snap-On torque wrench.
The piston protrusion problem has been well solved.
The head gasket will add 0.040" (1mm) to the deck.
<< | show individual entries | >>