PDA

View Full Version : 1st Engine Build



RacerBill
01-12-2009, 12:25 AM
OK, I have waited as long as I can. I am getting ready to do my 1st engine rebuild. The engine that I have to work with is a spare Shelby engine I bought when I needed some linkage parts. Everything seems to revolve freely.

Not ever having rebuild an engine, I have no idea where to start. The transmission is on the reace car now, and I removed the clutch and flywheel on order to attach the block to an engine stand. Got a box of zip lock bags and labels for all the fasteners.

I will call the machine shop tomorrow to find out how far to disassemble for what I want to do.

So, all you guys who have done this before, where do you start, and what tricks do you use for a successful rebuild. (and having someone else do it is not an answer, at least for me!).

Thanks

924Guy
01-12-2009, 09:15 AM
Definitely balance, blueprint, get the valves done (fresh valve job, or at least scrape the valves clean of any deposits and re-lap them in), check or replace valve springs... that's a start...

quadzjr
01-12-2009, 09:17 AM
The first question is "what do you want to do". Without that.. it is kinda hard to answer.

RacerBill
01-12-2009, 12:35 PM
Fresh engine - good power, not a hand grenade! I have been running with the engine that came in the car when I bought it back in 2001. Time to get some more power, and boot that car in the boot!

RacerBill
01-12-2009, 12:36 PM
Definitely balance, blueprint, get the valves done (fresh valve job, or at least scrape the valves clean of any deposits and re-lap them in), check or replace valve springs... that's a start...
How about port matching the head in addition to the valves?

MMiskoe
01-12-2009, 02:05 PM
The machine shop will want everything removed so they have fewer parts to keep track of. Just remember that you're paying them XXX dollars per hour to do what ever needs to be done.

Go look around for books on the subject. A guy named Tom Monroe wrote one that is pretty thorough and easy to read.

Keeping things clean while it goes together is a priority. Get a good beam type torque wrench. Don't touch bearings or bearing surfaces w/ your fingers. Do not be in a rush to do anything, take your time & be sure its right.

You've kind of asked an open ended question so its hard to provide specific details. I'm sure there are lots of things people can offer that they wished they didn't do which could be much more entertaining.

joeg
01-12-2009, 05:43 PM
Read the shop manual on "Engine/ Powertrain". As pointed out above, find buy and read books on engine building.

All the tips in such books are useful, even if the book is written about small block Chevys, or whatever. Why? because they all start with disassemby, inspection and cleaning, etc. (the basics).

Get yourself any special tools noted in the shop manual. They can be found cheap on eBay.

On any rebuild, get all gasket and seal kits off of eBAY--good deals can be had.

Always replace your waterpump, oil pump and timing stuff. LOOK FOR A NEW cam and lifters.

Buy an engine stand or two--they are not expensive.

splats
01-12-2009, 06:19 PM
Depending what year the block & heads are, MAKE SURE THAT YOU HAVE THE OIL RESTRICTOR PLUG IN THE BLOCK (OR HEAD). It only took me 4 engine grenades before we found the problem. Its a $5.00 part that cost me thousands. Without it, it will pump all the oil to the head & starve the crank yet still have 50+ psi. If you use the factory head from THAT block, you should be ok. If not, check it. Apparently, this is unique to the 2.2/2.5 mopars. And for the rule nerds, its a factory installed plug that just pops into the oil passage TO the head. No rules creep or violation.

quadzjr
01-12-2009, 06:23 PM
Depending what year the block & heads are, MAKE SURE THAT YOU HAVE THE OIL RESTRICTOR PLUG IN THE BLOCK (OR HEAD). It only took me 4 engine grenades before we found the problem. Its a $5.00 part that cost me thousands. Without it, it will pump all the oil to the head & starve the crank yet still have 50+ psi. If you use the factory head from THAT block, you should be ok. If not, check it. Apparently, this is unique to the 2.2/2.5 mopars. And for the rule nerds, its a factory installed plug that just pops into the oil passage TO the head. No rules creep or violation.


This also applies to hondas vtec opperation and othe engines as well! You machine shop will more than likely loose it or remove it during machining and cleaning the oil passages. Good tip!

quadzjr
01-12-2009, 06:57 PM
People seem to cover the basics.. What I can tell you is that you can never, never be too precautious. It takes me a nights few days to assemble an completely dissambled engine. I spend almsot one whole night on the head alone, matchign spring pressures and shiming the valves.

tips not mentioned thus far.

1- one of the most important is cleanliness. invest in a large garbage bags to cover all of your parts. I Fyo udont' have a parts washer make sure yo uclean every part throughly. make sure you chase every oil port in the crank, rods, everything.. Just the hot tanking alone will not clean all of these ports out.

2- assembly lube. make sure you are not to conservative with the stuff. yes it might get everywerhe.. but on any part that is no a roller bearing will benefit from the use of it.

3- Have your machine shop mark everything so that you can re-asemble exactly how he balanced it. also make sure that you get every single number from him. Main cleanrace, rod cleanraces, ring gap (If you don't do that yourself), wrist pin clearance, ring

You need to know what material rings you are going to run and the type of alloy pistons you are going to run. So he can finsih the bore with the right hone and match the cylinder to the piston and vise versa.

4- rings.. make sure that hte rings you choose to use are the right size for the ringlands in your pistons..

5- ALRIGHT... this list can go on forever.. If you have any questions.. you can PM with any. The only things I am decent at is racing ATV's and building engines. Typing without spelling errors jsut takes too much of my time! :D

Chip42
01-12-2009, 07:28 PM
The only things I am decent at is racing ATV's and building engines. Typing without spelling errors jsut takes too much of my time! :D

you're a hell of a cook, too.

Spinnetti
01-12-2009, 07:38 PM
How about read the IT rules? It spells out the mods you can do beyond the basics. Good news is you CAN'T build a "grenade" motor to the rules.. just an engine that will be "all it can be".... Good luck, its not as hard as it seems, and the machine shop does all the hard stuff. You just need to check a bit of the work and put it back together. Not mentioned, when you put the rings on, the orientation of the gap matters, so follow your shop manual closely...

quadzjr
01-12-2009, 09:32 PM
Everything I mentioned is not only legal.. but in my eyes important.. if you are going to spend the money in the machine shop.. Everything I mentioned is not of any additional cost to you, just your time. If you want to learn how to do it.. why not spend the time and do it right? :shrug:

P.S. I have built engines that I have thrown together under the direction of the person that I was doing it for.. but I make it aware of the consequences from every assumption that we make.

What if the hot-tank process wedged a piece of debris into the rod oil passenges..it woudln't of been the first time I have seen it.

Since this is your first motor build I would ask around to people in your area about a good machine shop. Which can either make or break this experience.. And NEVER assume that a machine shop will do something.. always confirm. Not that I don't trust them.. it is just yout money and time... not theirs.

joeg
01-13-2009, 10:21 AM
Those oil plug stories bring back painful memories...my plug was missing from the back of the cam.

Ruined my season.

Although the engine had oil pressure (on the lower side) I had run as low before without issues. Because the lifters were not getting proper pressure, however, all kinds of wierd stuff was going on in the valve train. Once in a while, as it reached a certain higher RPM, it would hit a hard rev limiter.

When I decided enough is enough and time to swap motors, I decided to take the old motor (actually it was brand new) apart in the car. After removing the hood and disconnecting all the ancillaries, when I got the cam partway out I could see the plug was not there. Talk about pissed-off.

I simply checked the lifters and reassembled. Full oil pressure thereafter. Of course then it developed other issues in subsequent race weekends...

RacerBill
01-13-2009, 11:33 PM
Yes, the engine being rebuilt is on a stand. That was requirement #1.

Tom Donnelly
01-13-2009, 11:40 PM
Those are all good suggestions.

Matching valve spring pressures. Thats a good one. Get several sets and test them to get a matched set. Return the rest to the dealship, unless they match and you've got a spare set. Balancing isn't all in the machine shop. Unless anyone knows of another way to match springs?

Keep everything clean. Really clean. Cleaner than I can at home clean.
Have good, well lit area (I like to see) with a decent workbench or engine stand. Lots of hand cleaner helps, the cleaner my hands are the better job I do.

Plan what you are going to do step by step, write it down and follow your directions. I write a to-do list, in no particular order, then sort it out in some kind of appropriate order and priority, including what I want done by someone else. A project plan I guess with checklists, materials needed and resouces. (Sounds too much like work but its saved me time and money). And before each step I ask someone more experienced than I for an opinion.

Go really, really slow. When I rush I screw up. And get books and RTFM.

I know I'm repeating others but I'm reminding myself too!

Chip42
01-13-2009, 11:52 PM
valve springs can be shimmed to provide for matched seat pressures. this is a standard practice, though it does get some people in trouble form time to time in classes like SM (runoffs). - just make sure shimming is called out in your FSM and you're DEFINITELY legit (I think should be legal across IT from 9.1.3.D.k, but if it comes down to service guidelines from the manufacturer a'la GCR 9.1.3D.p. then it better be in the FSM).

just measure your springs relaxed length and force at some fixed displacement and solve for k from F=L*k where k is your spring constant and L is the displacement where you measured the force (F) - try to use the fitted length of the spring as it would be in the head, valve closed (free length - closed length = L). get shims to make k*(l+shim)=F so that F is constant for all of the springs. your machinist should be able to do this for you or at least get you the spring shims is various thicknesses.

Tom Donnelly
01-13-2009, 11:56 PM
Is shimming IT legal? If it is then this is a great example of why asking questions is really important. Learned somthing new.

Chip42
01-14-2009, 12:05 AM
Is shimming IT legal? If it is then this is a great example of why asking questions is really important. Learned somthing new.

did an edit to the above. I don't know for sure if it is across the board, but I know that if it is a service procedure called out by the OEM, then it's 100% legal. I think it qualifies under "blueprinting," though it may count as an "addition" and therefor NOT be allowed universally.

quadzjr
01-14-2009, 10:32 AM
In either case if you don't want to shim your old springs to match them.. then you can buy mulitple sets of springs and get a matched set.

A machine shop can check these for you.. or you can build a valve spring checker your self. If you are going to be doing motor builds more frequently.. then you may want to invest in some of the specialized tools associated with engine building. (degree wheel, micrometere, digital caliper, ring compressor, ring filer, valve spring tester, etc...