General
There are still some oil marks on the engine block, so we change the intake manifold gasket. At Edelbrock, I order the new Edelbrock 7201 gasket set for around 30 EUR. I chose Edelbrock because I have Edelbrock cylinder heads and an Edelbrock intake manifold. In addition, we still need sealant. I decide to use a tube of elring Dirko-HT sealant. It costs around 10 EUR in Europe at the big online store.
In the garage, I check the steps and tools in preparation for the work. In addition, I take photos of the installed parts and any problems that may arise. To be able to loosen the screws of the intake manifold better, I order extra „nuts“.
Worth seeing and instructive are the two videos linked here, which I strongly recommend.
In the first video, the sequence starting at 5:10 minutes is the most important! And even more important: Absolutely follow what the gentleman does there!
Then it starts
Disassembly
Drain the cooling water and preferably collect it for reuse, or better yet, redo it. Disconnect the water hoses from the cooling water circuit and the heater, remove the carburetor connections and disassemble the carburetor. Loosen the alternator and swing it out to the side, then remove the alternator bracket. One or both valve covers may still need to be removed. The edges of the covers may interfere to allow easy and straight placement of the intake manifold.
Special attention must be paid to the distributor, which twists when it is removed and must be reinserted in the same way. To know how it must be positioned, we make markings.
All eight ignition cables off, distributor cap down, distributor carefully out and observe exactly what happens. So far so good and also quite simple.
Now that the intake manifold is “exposed”, we loosen all the screws and remove the manifold. It goes surprisingly well. Now we can “see” into the engine. The old gaskets are removed and everything is cleaned, glue residue is removed and the contact surfaces are checked.
It seems indeed the rear rubber seal is not tight. There are also oil marks in the front but not in the amount that it is really leaking.
Finally, as previously recognized, the rubber gaskets are installed between the engine block and the intake manifold.
Edelbrock writes in all their instructions that when using their cylinder heads and intake manifolds, these rubber strips should not be used. Even the guy in the video linked above throws the parts away. Why they were now installed remains a mystery and a puzzle to me.
Reassembly
We draw on the surfaces of the seals the sealant as a “string” of 5 to 6 mm thickness, which should be placed around all openings. It is necessary to find the right measure. Too little and it will not seal, too much and it will squeak out everywhere. You can wipe it off well on the outside, but if it presses into the intake ducts and in the direction of the valve pushrods, it is very unattractive. The sealant should dry for a few minutes.
Then place the gaskets on the cylinder heads. On top of this, sealant is applied again and allowed to dry. Finally, carefully put on the intake manifold without moving anything!
The threads of the fastening screws – and only the threads – must also be pasted with sealant, also because the start of the thread of the screws is partly “standing” in the cooling water or engine oil.
We tighten the screws of the bridge in two rounds to the torque of 34 Nm (equivalent to 25 ft-lbs) specified (by Edelbrock), paying attention to the sequence. It goes clockwise from “inside” to “outside” (see the following picture).
The following day, you should check the tightening torque again.
Unfortunately, I have made no photos of the steps (was so in the madness). So there is only a photo of the already screwed intake manifold.
We position the ignition distributor and sort out the rest.
Final spurt. Completing the engine. Coolant hoses, fill water, install and align distributor, connect spark plug wires to distributor and set up carburetor. Make all connections.
Double and triple check that everything is where it should be. First start. Engine runs and everything seems to be tight. No coolant, no gasoline and no oil.
Before we pack up and put everything away, the ignition timing has to be checked and adjusted if necessary. Then we go for a short test drive. After the short trip to the parking lot, the ignition timing is checked again. Fits. Effort with two people a good six hours.
