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Haven't felt this ignorant in a long time...

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drooartz

drooartz

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I've been reading the Vizard book on tuning the A-series motor, in preparation for building up a 1275 for the Tunebug. I've never worked on the inside of a motor, so all this tuning/porting/air flow stuff is way the heck over my head. Been learning a lot, mostly trying to focus on the fundamentals so I will at least understand how it's all supposed to work.

That's one thick, heavy book! At least a little bit of it is sinking in. Plenty of time left, as I'm only just starting the hunt for an engine/transmission. Good thing! /ubbthreads/images/graemlins/grin.gif
 
& its real good for chocking your tires when you break down on the roadside!
 
Right with you Drew, I'm comfortable enough changing valves this winter, but cams and timing chains and that little thingy that comes out of the side.
As a result of too much exuberance, that's all I'll be doing to the motor (had BIG plans).
Good book nonetheless, but it should come in chapters of comfort level and competance.
Chapter 1 - The purchase = Explaining to your spouse what you have done.

I'll do a deal with you, we'll dissasemble our 1275s at the same time, then we can take turns posting the questions so neither of us, ahem, ask the same question twice?
 
i had plans to do the engine rebuild work myself. the problem i encountered right away was all the measurements and specs to determine if the block and other subcomponents were within spec or not. after some discussion with the machine shop, i realized this was not going to be something i could tackle. i think though that when i restore my 65 (1098 cc) that i will attempt as much as possible. either that or just buy another 1275.
.
i will agree that trying to understand all the spec data is more than overwhelming.
 
This is easy folks. Take the block, the head, the crank, and the cam shaft, the pistons, and the rods to a machine shop.

Have them clean and boil all.

Check block bore for size and so forth and tell you if your pistons are ok or it will need boring and new pistons. Check crankshaft of main and journal sizes and and if they need reground or such. Same with crank bearings.

Now get what you need, new bearings in correct size, pistons maybe, rings, cam bearings.

Have shop level head and redo valves.

Have shop install new freeze pulgs in block and head.

Now if this is a good machine shop he will check your parts to see that all is ok.

You can either assemble your self or have the shop install pistons and rings and crank and camshaft.

I am sure you can do the remainder easly enough.

Gosh, lots of typeing, what did I forget.
 
[ QUOTE ]
Gosh, lots of typeing, what did I forget.

[/ QUOTE ]

Er. the cost?
That sounds expensive Jack, I'm not immune to the fact that spridget owning is not cheap, but boy....it really does sound like a huge job to someone who (me) hasn't done it before. Y'all be there for me if I do this, right?
 
one of the problems i found (and it might not be considered a real problem), was that even when i wanted something cleaned and returned to me the machine shop found either something that was damaged, worn, or out of tolerance. as a result, it wasn't as easy as just getting things cleaned and returned. i found myself depending more and more on the machine shop to correct the problem and/or install the new part. valve guides, detonated pistons, worn bearing surfaces, camshaft wear, frozen bolts and on and on. i tried to do as much as possible but it soon was evident that the machine shop was the way to go. after all was done, i have a great looking engine with a little more HP and a whole lot of new parts.
 
If I remember correctly the actual machineing including refaceing the flywheel was like $360.

Boreing and honeing cylinders. installing new cam bearing. Checking crank and journals, did not need ground.
Rebuilding head, installing valve guides and fitting valves leaveling head.
Resurfaceing flywheel.
Boiling all to clean.
Providing and fitting new freeze plugs, head and block.
 
Forget the freeze plugs? I'm not even sure quite what they are in the first place. /ubbthreads/images/graemlins/grin.gif

Barry, I'll be right there with you. I am planning on having a machine shop do most of the work. I'll probably try the reassembly myself, but I don't have machine tools or measuring ability to the level of accuracy that is required for any of the grinding work. Mostly I'm trying to make sure I understand what is necessary so I can ask the good questions, and understand the answers.

I'll be counting on all y'all for advice on specifics when I get there. For now, it's a question of absorbing the information and continuing the hunt for a motor.
 
Yup, this thread is being saved and I'll be following this path.
I just pray there's nothing wrong inside that motor that'll send me over the $500 mark, it hasn't run right since I drove it 40 miles home on 3 cyls following an argument with a plug wire, ooops.


[ QUOTE ]
I'll be counting on all y'all for advice on specifics when I get there.

[/ QUOTE ]

I'm counting too, I think we'll be fine.
 
Do replace freeze plugs, they rust out and then you will leak water, they are very very cheep.
 
What are Freezplugs???!
 
Freeze plugs are metal discs (4 if I remember in a 1098) that are press fit into the side of the block. They are the "weak link" in the cooling system. If the coolant freezes, it expands. The freeze plugs pop out, so the block doesn't crack. Easy enough to replace. Put it in the hole, smack it good with a hammer, and run a thin bead of sealent aroud the edge. One of the plugs is on the back of the block, so you have to remove the gearbox.

Don
 
I'm having some ethical problems already with what I've just gotten myself into.
What started as a desire to replace valves and clean the head to be more 'gasoline' compliant, has turned into an engine rebuild. I guess I akin it to removing an appendix when there's no symptoms. Hundreds of "what ifs..." are running through my head that this could turn out to be a 12 month lesson in 'what not to do' along with a financial nightmare.
I'll take baby steps on this one because I know my comfort level. I'll take the head off and see what I can see from there in terms of what it looks like and what it should look like; don't mean to chicken out on you Drew, but I'm almost certain that when I take the head off, some overpowering desire to continue stripping will previal until I have a large empty space under the hood.
What the hey, I need to replace that synchro in the tranny anyway.
Where's that 12lb lump hammer?
Spridget Forum, please prepare for mood swings, illogical outbursts, unreasonable behaviour and talking to myself in the corner of the garage; please keep me straight.
 
good decision and to be honest, it's going to be hard not to try and do more once the first parts are disassembled. That's one of the problems. you figure since you have the head off you'll just take a quick look at this and that and before you know it, you are digging deeper. take your time and do only what you really feel is necessary. for me, i am rebuilding the entire car. everything is either repaired or replaced. for that, i wanted a rebuilt motor.
 
Droo,
You might want to talk to Hap about motors before going too far in the dark. It just might make everything a little less painless. IMHO
 

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Barry,
It's a machine, you ARE smarter than the machine!!!!!!!

If I can successfully rebuild a moter, you can too.

Get a good manual. Start at Step 1, and follow the procedures in sequence.

You will break something, no big deal. You will find more stuff wrong than you thought you would. That is GOOD. When you are done, you will have a better machine, more self confidence, the ability to do more of your own repairs , and more knowledge than you ever dreamed about.

HAVE FUN!!!!!!!!!!!!!!!!!!!!!!!

Don
 
Baz, we've all done it the first time. We are here for you. Make sure you document with photos the entire removal for reference. Also look at the manual a lot and sleep on anything you are not sure of.

Again remember, we will help.
 
I'm planning on having a nice long chat with Hap before I get started. Once I have a motor in hand, I'll be doing a lot of very specific planning before a wrench ever gets turned. I figure if I'm doing the rebuild, I might as well do it right.

Barry--plan on pulling the motor. Isn't supposed to be too hard, and once you start messing around, you'll want to do it eventually. My understanding is that it's not too hard to pull anyways. Doesn't cost anything, either.

My advantage here is that I'm starting with another block, so I can still putter around in my car while I'm building the new motor. Once done, I'll swap it in and store the original 948 for future use.
 
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