Rudeboy's Engine Rebuild Thread
 

So as some of you may already know I've been planning on buying an engine to rebuild and put in my car. Well I got the engine on Saturday (2/13) and it's now in my garage ready to be torn into. The engine's out of an '87 944NA which is the same year as my car.

I haven't done much to it yet but here are so pictures of when I got it.[IMG]http://i698.photobucket.com/albums/v...s/DSC00078.jpg[/IMG]
[IMG]http://i698.photobucket.com/albums/v...s/DSC00069.jpg[/IMG][IMG]http://i698.photobucket.com/albums/v...s/DSC00045.jpg[/IMG][IMG]http://i698.photobucket.com/albums/v...s/DSC00041.jpg[/IMG]

I'm planning on taking my sweet ass time with this project, partly because of time partly because I want to make sure I get it done right the first time but mostly because of money, so don't expect me to update this thread everyday.

If you have any questions or advise feel free to let me know. I want this thread to be both helpful to myself and anyone else who is planning/doing an engine rebuild.

A motor I rebuilt started out looking just about like that.

http://forums.pelicanparts.com/uploa...1266260256.jpg

It's a fun and rewarding process.

That sure is perrrdy Schumi!

Please tell me about the rims on your car. I am interested in the offset numbers / spacers used and other info. I know they are a 928 item but please take it from there.:confused:

Can anyone help me by telling me how to get the bell housing off? I read that you need to thread an 8mm bolt into the release lever pivot shaft but how? An 8mm bolt won't fit in there. Is there something I'm missing?

It's possibly rusted shut.

Al alternative is the reach into the starter hole and undo the pressure plate bolts (requires turning the crank) and the pressure plate/bellhouing will all come off together.

Then a stuck clutch pin can more easily be extracted on a benchtop.

It's actually a M6 bolt that threads into the shaft. Removing the pressure plate bolts through the starter hole works well. Then you can soak it in penetrating oil. I tried extracting it with the bolt, but mine was too stuck. A 1/4" punch and a BF hammer through the hole from the other end made quick work of it.

i think those are either called Design 90 or Sewer Lids, can't remember
I also have seen them on 944S2's

Sewer lids... I have them on my car.

some like it hot
 

try heating it and quenching with penetrating fluid a few times, then heat it and show it who is boss. They are pretty stubborn. Vice grips and a larg(ish) hammer usually does it. Dent puller is an option. If it is really stubborn, hit it with pen fluid and come back later. Clean the threads and make Sure that you have the bolt well in there before going too wild.

Correction / clarification, heat the area AROUND the shaft, quench the shaft, thread the bolt and go to town.

I tried removing the pressure plate bolts and it worked great. Thanks for the advise guys. The only problem I had with it was that one of the bolts got stripped and I had to drill the head off. I started drilling into the shaft too but I realized the head was the only thing holding it on. Anyways I pried the bell housing and it fell right off and my frustration from the past few days went away as soon as it hit the ground. Then I took off the flywheel and now its finally ready to go on the engine stand so I can get some real work done:D

As far as my wheels go they are sewer caps, I've also heard them called D90s or seven slots. I'm not sure what spacers are needed for them or much else because they came with the car. Personally I think they're ugly and I bought a set of phone dials from the guy I got the engine from. I'm getting rid of them as soon as I get tires for the phone dials.

They would make good winter wheels if you get any snow in your parts. I never thought they were very attractive either. I'd definitely buy them if winter wasn't almost over.

Yeah I think I might save them for next winter. But I also might use them in the summer for autocross, if I decide to do any this year.

I hope the internal parts aren't as rusty as some of the stuff on the outside looks. At least you don't have to worry about the block having pitted cylinder bores.

P.S. I don't think porsche would appreciate use of the term "sewer lids" to describe their 928 wheels. I'm sure that they would prefer if you would use the term "manhole covers".

Anyways, back to the engine... I finally got it on the stand today after a quick trip to the hardware store for a longer 19mm bolt.
[IMG]http://i698.photobucket.com/albums/v...s/DSC00115.jpg[/IMG]

Once it was on the stand I vacuumed out the rats nests under the intake manifold. then, I took the exhaust manifold off, which was extremely easy with the engine out of the car. And just now I took off the belts and rollers along with the water pump. I did this a few months ago on the engine that's in the car. Since I knew what I was doing it took me all of a half hour to do.

So here's what it looks like so far:
[IMG]http://i698.photobucket.com/albums/v...s/DSC00120.jpg[/IMG]

Looks cleaner than mine did. Cooling system looks promising given how clean the block is behind the water pump. The head looks cleaner than the rest of the block. I wonder if it was rebuilt.

Yeah I was happy when I saw that it was so clean behind the water pump. The rest of the block is about as dirty as I expected it to be. The only really bad thing is how many bug are in the engine. It's been sitting outside for the last three years so that kind of stuff is expectable.

I wouldn't be surprised if the head was rebuilt not that long ago. I was told the owner who's car the engine came out of took good care of it so maybe he wasn't lying. I guess I'll find out soon when I take it off.

Hey that's a nice specimen, externally speaking! How would you like to clean this one?

http://forums.pelicanparts.com/uploa...1252293990.jpg

Just make sure you do clean it before tearing it apart. It will be ALOT easier to keep the insides clean with all the dirt and grime gone and you won't be washing it into internal cracks and crevices trying to clean individual parts. Just duct tape the intake/exhaust and other ports leading into the engine and scrub away. Engine brite or super clean works well. Soda blasting is one of the best I hear if you have a compressor. Once you get inside, you absolutely must be obsessive about cleanliness at all times! I spent probably half the time put into my rebuild just cleaning, cleaning, bagging, wiping down, more cleaning after certain jobs, cleaning again. It gets even more critical when you get into final assembly. Assorted sizes of ziploc bags and a sharpie are almost a necessity for keeping the smaller parts organized, protected, and clean. Just one piece of grit left in the wrong place and you put a big scratch in your brand new bearings, cylinder walls, crank journals, etc. on startup. It doesn't take much.

Also remember nothing ever fell off the floor. I did alot of the work on the ground on top of drop cloths, unfolded cardboard boxes, paper shopping bags, etc. for exactly this reason. Stuff like pistons, main bearing girdle, cam, and crank absolutely should not be dropped. Not only for the obvious reasons of scratching precision surfaces, but especially the cranks and cams are maleable enough (and heavy enough) to be bent if they take any kind of a spill. Be careful and take your time.


Luckily it was much cleaner on the inside. You may get lucky with the head like I did. Mine was recently rebuilt, still clean outside, even had a waranty badge with the name on it glued to the side of the head. I just cleaned it up really well, did some minor porting/surface cleanup, replaced valve stem seals, and lapped the valves. It definitely had the exhaust valve guides replaced. They still felt a little loose but still in much better shape than the guides on my old head. She runs very strong. It's almost hard to believe it's just another 9.5:1 CR 8v motor after driving my old one.

So I cleaned up the engine today and I'm quite pleased with the results. I used a total of four cans of of NAPA brand engine degreaser.[IMG]http://i698.photobucket.com/albums/v...s/DSC00129.jpg[/IMG]
Most of the grease came off but, there's still quite a bit of dirt left. I'll have to blow it all of with the compressor another time.

I just got finished taking the intake, fuel rail, wiring harness and most of the vacuum lines off. I was planning on just taking the wiring harness off quickly but, it turned out it was easier to get it off without the intake. It's exciting to see it without the whole intake on, it looks completely different now. I'll post pictures tomorrow when I have more time.

For now though I have a few questions:
1) Does anyone know where I can find a good diagram for the wiring harness? I did an ok job labeling where everything came from but there were a few wires I wasn't sure about and I'd like to have one around for when I put everything back together.

2) As more of the engine comes apart I'm starting to think more about what I should do for machine work. I'm thinking about sending everything to Lindsey Racing because they are very experienced with 944's. Does anyone else think this is a good idea? Has anyone else done this or know of an better place that they had a good experience with?

3) What should I get machined? Should I get the head machined or would it be cheaper to just buy a rebuilt one? Should I get the cylinders machined? I've heard mixed responses about whether they can or can't be machined. Can anyone clear this up? Lastly, should I get the crankshaft lightened or not? I've heard it makes for faster revving and better throttle response but reduces low end torque. Would it be worth it to do this since I'll be mostly driving it on the street?

Any advise is greatly appreciated, thank you.

I would have rotated the crank right there on the yard, if it felt good then seal the motor with new sleeves, mylar washers, o-rings, anaerobic sealant, belts pump, new rollers, and thrown it in the car. Don't for get the oil cooler seals.

But to answer your question, I wouldn't spend money on machine work, just parts. Change the rod bearing though.

I'm definitely going to replace everything you said and maybe more. I'm still open to suggestions on what to do since I haven't gotten into it too far yet and I'm not sure what condition the internal parts are in. I think that I still want to at least machine the head since I'll have the whole engine apart anyways and I want to do a very thorough job while I have the chance.

Has anyone else had any machine work done? Or think I should or shouldn't get it done?

I tried to take the head off today but I'm having some trouble. All the bolts came off fine but the head still won't come off. Does anyone have any advise on how to get the head off? Also does it have to come off with the cam housing on or can I take that off first? I tried taking it off first but it seemed like there was something holding it on from the other side.

The only other trouble I ran into was two more sripped allen bolts. If anyone else ever runs into an allen headed bolt with a stripped head(which you probably will), I recomend drilling it off with a 3/8in. bit. I've found it's the ideal size for 6mm allen bolts, which are the most common size on these engines.

hit it with a rubber mallet to see if you can break it free.

You might find this useful when you get around to installing the cam housing. Some good reading anyway. Go to their Tech Article Section,

Welcome to Dieter's Web site

Cheers,
Larry

I'd have the head machined. Should run you between $100-$200 depending on the going rate in you area and if you need valve guides. You'll want to ensure your head has the updated ball valve (oil) which it should if it's the proper head for the '87 engine. Check your cyl walls when the head isoff. If they are not scratched, I wouldn' bother with cyl walls, rings, main bearings unless you are planning to drop some coin and build something special. Once you pull that crank cradle, you need to know how to realign it to put it back.

Did you say that you removed the head bolts but your cam housing is still on?

Take a metal hammer and a drive pin at tap your Allen head bolts befor removing them. Sometimes it helps break the corrosion bond. It's to do with steel and aluminum in contact

Thanks that article looks really useful, I'll check it out again when it's time to put the cam housing back on.



Yeah I tried to take just the cam housing off first but it wouldn't budge. So, I tried taking the whole head off but had the same luck.

I tried to get the cam housing off again today by hitting it with a rubber mallet all around and gently prying it but, had no luck. So, then I just spayed the whole thing with penetrating oil and hung the whole engine upside down (with the head bolts on finger tight just in case it does decide to come loose). I'll try loosening it more the rest of this week and see if it'll come off this weekend.

BTW: Good call on using the punch to loosen bolts. I tried it out today and it worked much better.

If your cam housing is still on the head, then half of your head bolts are not accessible. Which means you removed Half of your head bolts all on one side of your head...which means you did not follow the sequence.

I'd suggest you stop working for a bit and spend some time on clarks garage reading about the proceedures related to the job you are attempting. You'll save yourself a lot of time, frustration, and money in the long run.

To answer your question, you need to remove the cam housing in order to access all of the head bolts. The cam housing Allen head bolts along the bottom outside of the housing and inside the housing accessed through the alum plugs on the top

Wow, I feel stupid now. I forgot about the bolts behind the plugs on the cam housing. I didn't look closely at the article on clarks garage at first, I just kind of skimmed through it. Normally I'm pretty good about doing research before I do work but, I guess I got a little over confident for a second there. Thanks for putting up with my temporary stupidity, I appreciate the patience.

Anyways, I got the cam housing and head off today with no more problems.:)
Then threw the lifters in marked containers filled with oil.

Working on this engine is starting to get addicting. If I didn't have to get up early tomorrow I'd still be working on it.

I follow this thread with great interest! For my own 944 I need at least a new head gasket but maybe more... So everything in this thread is very interesting for me.

However, you would really make my day(s) if you put some more pictures in your postings! I'd love to see how it comes apart and how it looks when it's getting back together.

Enjoy your rebuild!

Regards,

Koen from The Netherlands (360 miles from the factory where your engine was assembled probably.)

kvcuijck,

Look here for lots of good pics and write up on a rebuild too:
http://forums.pelicanparts.com/porsche-924-944-968-technical-forum/487924-project-924-s-engine-replacement-2.html

Sorry about that kvcuijck. I've gotten a little lazy with my posts lately. I guess I've been getting too caught up in working on the engine, it's too fun not to.

Here's some of the most recent pictures:

This is the bottom of the cam housing with the lifter still in:
[IMG]<a href="http://s698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/?action=view&current=DSC00178.jpg" target="_blank"><img src="http://i698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/DSC00178.jpg" border="0" alt="Photobucket"></a>[/IMG]
I didn't have any problems with them falling out when I took the cam housing off but, it's a good idea to have someone help you catch them and remember where they came from.

Here's the the housing with the lifter out:
[IMG]<a href="http://s698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/?action=view&current=DSC00179.jpg" target="_blank"><img src="http://i698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/DSC00179.jpg" border="0" alt="Photobucket"></a>[/IMG]
They come out pretty easy even though they're slippery with oil. If you have any trouble getting a grip on one you can just turn the cam shaft to push it out a little further.

Once they're out make sure you know where they came from in the cam housing by marking them. Also, you have to keep them in oil because otherwise it takes a few minutes for them to get oil when you start the engine up again. And as we all know no oil = bad news. What I did to both keep track of them and keep them lubed was use eight small containers, individually marked, kept one lifter in each and filled them with oil. It only took about a quart of oil.
[IMG]<a href="http://s698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/?action=view&current=DSC00177.jpg" target="_blank"><img src="http://i698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/DSC00177.jpg" border="0" alt="Photobucket"></a>[/IMG]

These are the cylinder head bolts:
[IMG]<a href="http://s698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/?action=view&current=DSC00180.jpg" target="_blank"><img src="http://i698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/DSC00180.jpg" border="0" alt="Photobucket"></a>[/IMG]
[IMG]<a href="http://s698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/?action=view&current=DSC00181.jpg" target="_blank"><img src="http://i698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/DSC00181.jpg" border="0" alt="Photobucket"></a>[/IMG]
Remember to learn from my mistakes and take the head bolts off in the correct order! :rolleyes: And if the head doesn't want to come off at first gently pry the tabs on the sides. Don't pry the gap between the head and block because the soft aluminum can be damaged easily and the head won't seal properly anymore.

This is what it should look like once the head's off:
[IMG]<a href="http://s698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/?action=view&current=DSC00186.jpg" target="_blank"><img src="http://i698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/DSC00186.jpg" border="0" alt="Photobucket"></a>[/IMG]
From there the gasket shouldn't be too hard to get off:
[IMG]<a href="http://s698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/?action=view&current=DSC00187.jpg" target="_blank"><img src="http://i698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/DSC00187.jpg" border="0" alt="Photobucket"></a>[/IMG]

And here's what it'll look like once the gasket's off:
[IMG]<a href="http://s698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/?action=view&current=DSC00188.jpg" target="_blank"><img src="http://i698.photobucket.com/albums/vv350/Rudeboy42/Engine%20Rebuild%20Pictures/DSC00188.jpg" border="0" alt="Photobucket"></a>[/IMG]

Hope this helps kvcuijck and anyone else who is thinking about taking their head off (no not that one) < too cheesey?

Anyways, if anyone would like any specific pictures feel free to ask, I've got plenty I still haven't posted.:)

@ddbach: Thank you for the link!

@Rudeboy42: These kind of pictures make my day every day ;) Did you run into area's that really need some work? How are the cylinders from the inside?

Go ahead and post some more pictures:)

Regards,

Koen

And?

How's the rebuild coming along? Love to see some fresh pictures ;)

Regards,

Koen

Sorry, I haven't posted in a while, I've been getting a little side tracked lately. I've been fixing some loose ends on other parts of the car so the engine project has been taking a back seat (a very small one, lol). Also it's been really nice out so I'm more tempted to drive the car than work on it.:D

Anyways, I'll get some more pictures up soon and let you guys know how it's coming along.

The picture of the cam housing with the lifter removed made me do a double take...is the tip of that cam lobe actually tapered off from wear on the rightmost third or is that just a reflection that makes it look that way?

Looking good so far. ;)

I think it's probably a reflection of the round hole you're viewing it thru.

yeah Aufenbahn is right it's just the reflection from the hole. That'd be scarry if it was that badly worn though.