83 n/a 944 ...No crack?

bobbydirl · 01-26-2010, 07:40 PM

Got the head off today. (Re: 83 n/a 944 ...hg??) I saw no crack/s in the head or in the block using the naked eye.

1. But, what I did see was that the studs on the driver side of cylinder #3 showed rust at the base where they go down into the block, and that the exhaust valve for #3 was steam cleaned.

Question 1. ... Could this account for a history of very slow coolant loss? The gasket looked pretty good too. What about a warped head?

2. Recently a rapid coolant loss occurred over a week's time while it was sitting in the garage. Thinking that I might not have purged it right, I topped off the coolant. It leaked down again in a day's time while still sitting in the garage.

Question 2. ... Could an oil seal failure account for this relatively sudden loss of coolant down into the oil pan?

What I am thinking now is head gasket kit and oil cooler kit. What do you think??

Rasta Monsta · Rasta Monsta's Garage

I don't think I'd classify that HG as "pretty good."

Grandad#3 · 01-26-2010, 09:34 PM

Be prepared to take your time cleaning the engine block and not nick the aluminum surface.

Cheers,
Larry

porsche4life · porsche4life's Garage

I don't think I'd qualify anything I see there as "pretty good" I can see a hole in that HG from here... Next to the far right cylinder...

bobbydirl · 01-27-2010, 05:57 AM

Thanks Mosta & 4life.. mia culpa, it's the first gasket job for me. I saw a picture of one here that had virually nothing left but the metal rings around the cylinders. I guess that's what I expected to see. Let me ask, ...does it look bad enough to leak coolant down into the oil pan?

Also, thanks to Grandad for the advise. As for cleanup, I have a small tub sitting under the motor to catch stuff capable of staining my garage floor. ...to catch drippings from Simple Green... do you have any better ideas?

Thanks, Bob

AA_Ezra · 01-27-2010, 03:04 PM

You Can clean the Piston tops with Gasket Remover and and Non Marring Gasket Scraper set from like Harbor Freight Come in a set of 5 i think and they are bright Orange.

This is what I did
1.Find TDC for the pistons Cylinder 1 and 4 will be both at there highest point. Same for 2 and 3
2.Put some Grease around the piston being sure to cover the space between piston and piston wall so that any gunk will get in the grease and not into piston grooves which you can later remove after the piston goes back down.
3. Get some Gasket Remover ( CRC Brand works awesome) Its in a can so i sprayed it in a container then scooped it up an put it on the carbon deposits on the piston being careful not put to much and let it run off. Let it sit for a while, i waited about 10 min maybe more or less depending if the gasket remover is drying.
4. Scrape the gunk off the pistons with the non marring scraper wipe what you can and vacuum anything you might need to and keep repeating the same steps until you're happy with the results.

5.Bring the pistons down slowly cleaning off the grease with a clean rag ( big box of rags) I then used a rag soaked in Brake cleaner to make sure it was really clean.

6. soak a rag in some Carb cleaner and clean up Burned stuff around the top of the cylinder walls
7. Spray some wd-40 on another clean rag and wipe the cylinder walls and piston tops so that when they travel up they will be lubricated and you can do the other pistons. I guess very light motor oil on a rag would be bette.

That's just what i did and i was very careful not to get grease on the outside of the pistons were the coolant flows and the same for the oil passages. You can try it or pass its up to you

Regards
J

Ps check out my threat with pics of before and after piston cleaning
http://forums.pelicanparts.com/porsche-924-944-968-technical-forum/514873-clicking-tapping-sound-engine-stumbles-then-poof.html

bobbydirl · 01-27-2010, 08:09 PM

Thanks EZRA. I will check out the CRC. I started with the razor blade tonight, just on the intake manifold inputs to practice a little before getting to the larger surfaces. Your gasket looked almost decent compared to mine. Looks like I have a lot or rust compared to yours in the pictures.
... Bob

HondaDustR · 10:31 PM

If it were me, I would take it to a machine shop and have it Zyglo checked for cracks just to be sure, given it was leaking so badly into the crankcase. It could be hairline cracks that aren't obvious to the naked eye that may widen at operating temp. Also have it checked for warpage as usual. Other than that, it's just cleaning, cleaning, cleaning, as mentioned above, and reinstalling the head with a fresh gasket. I wouldn't worry too much about the rust around the base of the studs. Just clean it out. It's probably moisture leaking by the gasket. Some had suggested to me to use the copper gasket spray on the head gasket when I did it. I used it and have had no problems. I would recommend it as a little extra insurance. Just a light coat...

Interesting fact you might notice is the cylinder head is a bit softer and easier to nick with the blade while cleaning. I believe only the block is cast in the Alusil alloy. It feels a bit harder and dulls blades quicker.

Any WYIT plans? Lap the valves, new valve stem seals, etc. Personally, I'm very obsessive about cleaning caked on oil crud to make the motor look as well cared for as possible and those pics make me cringe a little. No better reward for fixing leaks than seeing it stay clean. Perfect chance to do it.

Good luck!

bobbydirl · 01-29-2010, 07:24 PM

Thanks Honda. I have a few WYIT plans floating around the back of my mind from reading so many threads here.
1. Today I went to O'Reilly's to get CRC, Seafoam and Assembly Lube to follow the suggestions from EZRA on cleaning piston tops. Right now the engine is at TDC and I can see no problems with the sleeves for #'s 2 & 3. After I clean and secure any harmful carbon chunks at #'s 1 & 4, I will rotate the crank until I can check their sleeves (checking for cracks that might allow coolant into a wrong place). I have drained the coolant from the block with the passenger side bolt and have gotten most of it out with your paper towel method, down below the passage up front that goes to the water pump.
2. Please keep that in mind as I tell you that I am still getting coolant rising up the oil cooler drain hole to the oil filter attachment point. In my mind it must be coming from coolant being held in the water pump by the thermostat and allowed to seep past oil cooler seals, .... or ...SHUDDER! ... a hole in the block at that level. It seems impossible, but to be thorough, I am not committing to any WYIT options until I have removed the oil cooler and have become confident that any monies spent will not be wasted. Being on fixed income and having been really burned by dealers and "professional" technicians over this car for the last 26 years have taught me to take things r..e..a..l..l..y s..l..o..w. I have spent more money at dealerships since 1983 than this car originally cost. So far all I have spent is for a few sockets I was missing and some cleaning materials. If all goes as I expect, I plan to do a head gasket set and oil cooler seals. All the front end stuff was done less than 2k miles ago by a local rip-off Porsche dealer (Ouch!)

..don't get me start about the elitists.

porsche4life · porsche4life's Garage

Just because the local Porsche dealer just did the front end doesn't mean squat here.... A 27yr old gasket failed... thats what they do.... The dealer wasn't into the motor that far....

bobbydirl · 01-29-2010, 07:33 PM

Honda was asking about WYIT things which I assumed he meant front seals, belts etc.,.

HondaDustR · 09:48 PM

Quote:

Originally Posted by bobbydirl

Honda was asking about WYIT things which I assumed he meant front seals, belts etc.,.

I was thinking more specifically head or valve work and cleaning the outside of the block, but lots of things can qualify as valid WYIT possibilities at this point.

bobbydirl · 02-02-2010, 03:31 PM

Thanks Honda. Yes, I do intend to do valve work, the head appears not to be warped or cracked. I might get a spring compressor and do it myself. I was working on cleaning the outside of the motor today and discovered an item that prompted a question:
Is it OK for the cap on the rear of the lower balance shaft to be a little loose?
(see picture)

krystar · 02-02-2010, 03:43 PM

ok? no. it could be the seal is torn or completely gone. i wouldn't be surprised.

dC Automotive - You Porsche & BMW Parts source they're primarily a used parts warehouse but u can get all new seals and gaskets for pretty cheap there too.

tear your engine apart and see if it's worth fixing first. no point to ordering parts if there's a hole in the block

Techno Duck · Techno Duck's Garage

That rear cap is sealed between the balance shaft cover and block by an o-ring. That o-ring shrinks with age and causes the cap to get loose like that. To change that o-ring you need to take the cover off. Not a bad job for the upper, but the lower is a pain in the butt. You need to take the passenger side engine leg off and drop the crossmember.

Depending how bad yours is leaking, many people have luck with just cleaning the area very well and putting RTV silicone over it and letting it dry a day or so.

I think more than likely every 951 has that lower one leaking due to how close it runs to the crossover pipe. I know mine does..

.

HondaDustR · 05:37 PM

The o-ring likes to shrink with age. Replace it now while it's accessible. It's a PITA job otherwise. You'll need some locktite 574 case sealant or equivalent as well.

bobbydirl · 02-02-2010, 07:05 PM

Thanks guys, that would certainly qualify for a WYIT item. ...only after KRYSTAR's suggestion to verify no bad block first. However, barring bad block, I might just do the head and oil seals and boot it up to check for bearing damage. If I have to take the cross-member off for the pan (to get to the rod bearings), I could maybe get to the "O" ring then. If not, TECHNO's RTV might be the best. On the same note, if I do have to remove the pan and support the motor from above, what would be the most economical way to do that (besides borrowing stuff).

krystar · 02-02-2010, 07:15 PM

shop craigslist for a cherry picker. there's usually a good number of used ones if u look around.

Techno Duck · Techno Duck's Garage

You can come up with something easily with stuff readily available at your local hardware store. I used a few pieces of wood blocks as standoffs over the strut towers, a piece of super strut and some chain / hooks through the engine hoist rings,

AA_Ezra · 02-03-2010, 03:02 PM

I baught one of these and used a 15% off coupon you get by sighning up at there webiste for coupons. And I think it was on sale but on not sure. I thought it was worth it since it would make so many more jobs easier, pan gasket, motor mounts, suspention etc..
- Harbor Freight Tools - Quality Tools at the Lowest Prices