72 tii runs but clicking and no compression on 3 and 4

[sealions518]

I was driving to work one morning and all of a sudden I lost most of my power and the car is making this clicking noise (see video). No over heating and no oil light on. I limp her back home and check distributoar, wires, plugs, etc - and they are all ok. I then do a valve adjustment with no change. I am a newb to my tii (I've had her two years) so I am not sure if these are even good places to start. I checked compression and cylinder 1 is 160 and 2 is 145 - cylinders 3 and 4 are showing no compression whatsoever. Any ideas are points in a direction of further research? I have a shop I can take it to but hoping I can tackle some of the diagnosis stuff myself. It's been really sad as this was my daily driver

 

Thank you in advance!!

[Son of Marty]

Most likely a blown head gasket. 

[irdave]

That sounds like it's running on 2 cylinders...

 

I'm a newb myself, but I bet the answer is pull the head.  It's a pain in the can the first time, but it's actually straight-forward to do.  Down 2 cylinders could be a head gasket between the 2, something cracked...

[Mike Self]

Yep, that chuffing sound you hear is two cylinders that are no longer with the program.  Had that happen to my '73 (with exactly the same sound, and no power) due to a lean condition in #4 cylinder--head gasket was OK but it burned a passage through the head surface between #3 and #4 cylinder.  Fortunately a local shop welded up the passage, surfaced the head and all was well.  

 

So long as you're sure that there's not a problem with a valve in both #3 and #4 cylinder that isn't closing properly (unlikely but most anything is possible) then you're gonna have to pull the head to see what's going on...  

 

If you had good compression in those two cylinders and they were acting dead, then I'd suspect clogged injectors, but with zero compression...something's wrong inside there.

 

mike

[wegweiser]

Rumor has it, this job can be performed in one hour and fifty six minutes….by flashlight…outdoors…in the parking lot of a hotel. Being surrounded by the right friends certainly helps!

 

Definitely sounds like head gasket. Have the head checked for cracks / straightness before reinstalling, if you can afford it. I had to get mine home the next day, so I didn't have the option. 4 years and 50,000 miles later, it's still doing alright!

 

[sealions518]

Thank you for all of the responses - I love this community!! Any suggestions for things I should do while I am in there? This car doesn't have too many miles on a rebuilt motor that was done in the late 90s. Also, my speedo stopped working so I'll have to figure that out ha ha.

[wegweiser]

Purchase a "head gasket SET". Try to get Elring brand, as folks have had issues with the Goetze brand, on occasion. Resurface head, inspect timing chain tension (before removing head.) If it's a high compression performance motor, think about spending the extra money on a "cutting ring" head gasket - also sold by Elring / the usual BMW parts suppliers. 

[sealions518]

Thank you for the info Paul. It is not a performance motor - just a stock 72 tii that I can putz around in  I found an Elring from autohausAZ but it doesn't look like a set. Also, a lot of the other ones I am finding have different thicknesses listed.

[Son of Marty]

And as always if you resurface the head be sure to send the upper timing cover with it to be cut a equal amount 

[sealions518]

So I finally carved out some free time with my brother and manged to get the head off the car. It was very evident that despite having worked on numerous cars (Hondas) we are total newbs at working on a tii. It turns out that it was a blown head gasket between 3 and 4. I am attaching pictures for reference. My new questions are:

 

1. Anything in the pics that is screaming "take care of me?"
2. Suggestions on a reputable shop in SoCal to get it checked/surfaced? How much should this be?
3. Any "while you're in there" suggestions? I know I want to replace the exhaust at some point but not sure where to get that from. 

 

Thank you!!

['76mintgrün'02]

You won't have any trouble selling your old exhaust manifold!

 

Sorry, that's all I've got.

Tom

[irdave]

You're just trying to get it running?  Intake and exhaust gaskets to go with it...  Everything else leads to a very slippery slope.

[sealions518]

Yeah just tying to get it running. I should add that I still have no idea which gasket to get and how I go about checking my old one to know which one to get.

[jimk]

Be sure to clean the block heat bolt holes dry or the block can crack from hydraulic lock if holes have oil in them.

[Simeon]

Simplistically you just get a top end gasket set which should have everything you need (and maybe a bit more). 

 

Did you have any overheating issues before the gasket failed? You need to measure whether the head is warped or not before putting it back. A steel ruler and feeler gauges are enough but I can’t remember the values that you are shooting for. Search on here should show that. 

 

Clean the block face and head face well, you may as well clean the piston tops too.  Once done, clean out the bolt holes in the block. Do this several times with brake cleaner, bits of rag, compressed air - whatever you have to get them spotless. You want to be able to hand screw a bolt to full depth in the block when you are finished. This is important as it stops you cracking the block if you have fluid in the bottom of the hole and it ensures that the torque that you use is actually representative of how tight the bolt actually is.