oil leak 91 civic

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jdeshiro

New Member
im leaking oil from the rear corner of my head gasket right where the block meets up with the tranny.. new head gasket done right but the wierd thing is that its leaking as its parked... like now it hasnt been started in a week but it just keeps leaking out? any suggestions?
 
Chime. :)

Checked for flatness? Not ripping at you on that, but anything short of a machinist doing the work on a flat table with a dial indicator would be questionable for me. Checking the deck on a block for flatness using a straight edge like suggested in a Haynes book is pissing in the wind IMO. I don't know what you did or who did the work - just offering my opinion bro.

Calesta asked if they were decked? You responded yes. If it was decked and not just checked disregard above banter.

Before I did the swap on my ride last year, in the spring of 2010 I put a rebuilt head on it as a last ditch effort to pass emissions testing in June. It was burning oil from worn out valve seals and rings. After the head change it manifested much the same leak as you describe. My assumption is the head was flat and block wasn't. Oh yeah, it aoso blew a head gasket a couple of months after the head went on. Changed that and drove it another 6-8 months until I had all the $ for the engine combination I wanted.

There are oil wells in the head, and on the tranny side it puddles around where the dizzy interfaces with the cam. It can leach down a head bolt or whereever. In my opinion, it's an indication of things not being flat.

Did you use an OEM head gasket? When I did the first install of the rebuilt head I used the cheapest AutoZone gasket they had and it lasted about 90 days and let go between #3 & #4 leaking coolant into #3 when parked. As I recall, I bought the replacement gasket from AutoZone also, but picked up a better quality part the second time around with better results.

The car is a 1991 Civic Si and the engine was the stock D16A6 that was original with ~170,000 miles on it at that time.

When you installed the head bolts, were the threads in the block clean and clear of debris, rust, corrosion? Did you oil them up good on re-install? Or, better yet use Anti-Sieze on the threads? Did you warm it up and run for ~15 minutes, allow to cool overnight, and re-torque head bolts? Did you re-torque after 500-1000 miles of driving.

I do the back-off 1/4 turn to each bolt for the re-torque sequence to be sure they re-torque correctly.
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http://www.yotatech.com/f116/re-torque-head-bolts-211770/

"Other than simple overheat, the #1 cause of head gasket failure is clamping force variations.

Usually when I mention this, the answer is "I torqued it properly!"

*Yes, very likely, but torque, which is a twisting force, means almost nothing when we are talking about clamping force. Dirt or machinery debris in the bolt holes will throw the clamping force off as much as 50% and more, even though the torque wrench reads perfectly normal. The same happens when installing new bolts. The very best bolts made will show a rough mating surface at the threads when inspected under a microscope. When installing new or used fastners, first be sure the bolt will spin in and out ALL THE WAY freely with simple finger pressure. Be sure they are lightly oiled, not too much which can hydraulic lock at the bottom of any blind holes and spoil your day.

Use this simple breakin procedure for any new bolts: Tighten all of them to 50%, back off 1/4 turn, then to 75%, back off 1/4 turn. Then take them to 100%, back off 1/4 turn and repeat.

Do a retorque after full warmup.

*This procedure simply assures that the imperfections of the threads seat to the bolt hole threads.

Yes, time consuming, but much faster and less costly than another set of gaskets, the actual clamping force will increase vastly, even though the torque load is exactly the same.

The alternative is you may be additional twisting at the top of the bolt after the threads have come to a stop from excess friction.
If any single one does that, head gasket failure prematurely is gauranteed, plus it weakens the bolt....*EB"
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EDIT: Sometimes the head gasket can bunch up around the alignment dowels if they fit too snugly around them and not a perfect fit. That can cause problems.
 
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i had to do this swap all on my own with limited help other than for a cherry picker. funny mine is also a 91 civic lol.. the set up is as follows... i put the origional block back in with 100xxx on it.. never been overheated but it was pulled due to a bent valve and a buddy has a spare b16 laying around with 250xxx so it was easier to do the swap... car started and ran fine but the rings were going.what i did was put the 250xxx head on the 100xxx block and drop her back in.. what im possibly thinking maybe is during the head exchange i did bend a corner of the head gasket by head bolt #9 i believe.... bend was maybe a half inch from head bolt if that.. now knowing that is it possible i just ruined the gasket? lol that and i did buy the cheap autozone gasket too. knowing now that yours failed so soon is there another gasket brand you would recomend? I know cars but all cars are diff.. and im a lil knew to the honda game
 
Good gasket brands would be Cometic, OEM Honda, Fel-pro, Victor Reinz, in roughly that order. Make sure you use a MLS type gasket and not a graphite type gasket. Also you need to buy new head bolts or better yet buy a set of ARP head studs.
Honda has a TSB out about the head gasket problems on older d series engines and they recommend using the newer MLS type gasket and new head bolts.
BTW per the specs in my repair manual d series Honda head bolts are TTY type bolts and should always be replaced. That is why I love ARP head studs, they can be re-used as many times as you want.
 
As Fernpatch stated, MLS (Multiple Layer Steel) is the way to go for head gaskets.

Having dealt with failed head gaskets and the hassle of subsequent teardowns I use Cometic gaskets and also use ARP studs.

That's basically a $200 bill, evenly split between the two. I found the best prices for them on eBay.

The repair job on the blown head gasket for the D16A6 involved a "Better" grade Autozone gasket which worked out ok if you don't want to spend the $ for the high end parts. If you opt for a Cometic head gasket, they are available in different thicknesses - I believe 0.031" is the closest they offer to OEM stock. Confirm that before ordering.

Assembly problems happen to us all. I dorked up the lower bearing on #2 rod putting my new (used JDM with full rebuild) engine back together last year and it failed. Oops!
 
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