‘77 Corolla: head issues.

[wame]

• This is what the mechanic in Northern California reported:
   
• 77 corolla diagnostic- wont go over 35mph or up hills
• suspected coils or massive exhaust leak (back pressure) or head Gasket.

Note, checked and found Catalytic converter is broken internally. I did a cylinder kill test and found no.3 cylinder is dead, performed compression test and found both cylinders 3 and 4 have almost no compression, no.4 5psi no.3 30psi no.2 135 psi and no.1 with 145psi

Thanks RollaClub!!

 -wade

[wame]

[altezzaclub]

Definitely sound like head off and a careful rebuild. Note the tension on the exhaust manifold studs/bolts as you undo them, the head goes off for a skim and a valve job while you make sure the manifold studs are all tight.

A good idea would be to pull the block out while the head is off, tip it on its side and clean all the rust and debris out of the water jackets around #3 and #4 cyls, which is probably what gave the head gasket a hard time to start with. I did that to my K motor in here-

https://www.rollaclub.com/board/topic/42407-the-girls-ke70/

Not a big job really, although its easy to get buried in it as you think "I'll just check the clutch and maybe replace it, and there's a bit of a ridge on the cylinders so I should rebore and do bearings and..."

Edited September 13, 2025 by altezzaclub