Ferrari 400GT Reassembly



I reached out to Stephen Markowski to come up for a couple of days to my shop to lend me a hand on reassembling a 400GT engine I’m resealing from oil leaks. I’m still recovering from shoulder surgery, and although my recovery is going well, I’m still not quite 100% back up to speed, so having Stephen agree to visit was a big help. I’ve known Stephen for many years, and he began his career at his father’s shop RPM Vermont, and is now has his own garage space in the NYC area.

Not only did Stephen help me with moving things around my shop and wrench on things that I haven’t yet built up the strength to do, it was also good to have a second set of eyes watching the reassembly to make sure we didn’t miss something.

Like most Ferraris, they can leak oil and it’s no wonder when you see how much surface area relies on a good seal from a gasket or o-ring. As Stephen and I assembled the engine, we both carefully looked and checked the proper sealing was happening. Even with all this care, we crossed our fingers we did it right!

The o-rings on some of these sealing surfaces can’t be accessed without removing the head, or engine block, and with them approaching 50 years old, they have usually lost their elasticity, so leaks are inevitable. I installed new o-rings everywhere, along with new gaskets, sealing them with a gasket dressing Stephen likes.

Every mechanic has his or her favorite gasket dressing, while the factory often used none. When these cars were new, and the machined surfaces were fresh, flat, and not corroded, not using any sealant was fine but I don’t know anyone in this business today that doesn’t use some kind of sealant. I normally us a Hylomar product, and some RTV, but Stephen wanted me to try a Loctite product he uses and likes. Its always good to get an unbiased endorsement from a mechanic that has real world experience that I trust than a manufacturer’s sales pitch, or even a paid endorsement from an unknown mechanic!

These particular engines found on 365GT/4, 365GTC/4, 400GT, 400i, and 412 engines, all have this layout where the oil pump and water pump are driven off the crankshaft with a separate chain assembly. There are a number of sealing surfaces in this area that are submerged in oil, hence the propensity for leaks!

As we tightened the bolts, and watched the gasket sealant squeeze out, we again crossed our fingers we sealed it all!

While the engine was being assembled, I worked on cleaning a lot of the little pieces that needed attention. I ultrasonically cleaned the carburetor velocity stacks so I could soften the gasket material so new gaskets could be installed.

The submersion in soapy water helped soften the old gaskets but they still needed to be scraped.

A new coat of wrinkle paint was needed for the valve covers, so stripping and masking the covers were the first steps.

Everything gets painted black wrinkle, and don’t even think about polishing the Ferrari letters shiny!

My first attempt was a failure as a brand new can of VHT Wrinkle Paint had a faulty nozzle. It dripped more than it sprayed, but with wrinkle paint, once you start, you can’t stop, so I soldiered on.

Hoping if I applied enough paint, the drips would not show up, but I was wrong. The wrinkling process requires a specific temperature, and a very thick even coat of paint applied almost to the extent of running, but the uneven drips from the faulty nozzle showed up despite my best efforts.

I stripped all the paint off the valve covers and started again, with the second attempt with a new can of paint a success.