Nemo Head Install

Recall my prior post about Nemo, T's 1997 Audi A4 (See Sadist Engineering), I had exhausted all alternatives and had taken the plunge to remove the head to replace the head gasket. Today's post covers the re-install.

Head Shop

No, not that kind of shop, though I am in Oregon.... This head shop does work on the heads and block of your car. I looked around and found a small one-man operation 15 blocks from my house: Wilson Cylinder Heads and Machine. I figured that if he did good work (like according to the reviews), it would be really great to have a machinist so close. Keeping the money in the neighborhood is very important to me too, as you've probably noticed. Anyway, I dropped off the head and we talked a little bit about it. Since the car had not been misfiring nor throwing codes, he was not angling towards a rebuild. We turned it over and he could see that the center 2 cylinders had suffered coolant leaks, and figured that was caused by a head gasket failure. Remembering that the head bolts were none-too-tight, I was starting to think that the head was redone at some point by the PO and it was not torqued down properly. Recall, the PO did upgrade the suspension and the turbo, so maybe the head was redone at the same time? Anyway, Luke (the owner-machinist) went through the head, looking at the cam shafts and valves etc while he did the pressure tests and tests for cracks and other failures. The head came back clean. So, with a complete gasket kit in hand, but only a small subset really needed, I picked up the head and set to re-installing it.

Exhaust to Head

After the troubled removal, I decided that I would install the exhaust manifold (with a new gasket from that kit) to the head before putting the head into the car. While the head was at the shop, I scrubbed the manifold with sandpaper, freeing it of rust and then shot it with flat black header paint. It looks much better now. Before mating the manifold to the head, I put the turbo bolt which sits closest to the head through the manifold. It won't go through after it is attached. I installed all of the fasteners (random so they may be) and torqued them to spec. Once attached, the head is heavier, which is saying something because a fully loaded head is already pretty heavy already. I verified that the head was still in TDC position by setting the valve cover on, and checking the dimple on the gear aligned with the dimple on the cover.

Prep Engine
None of the online advice I have seen specifies the use of any liquid sealant for the replacement of a head gasket. It appears that this was popular in the past, but gaskets have gotten much better and tolerances have gotten much tighter, so if you are doing this and think you need a sealant applied to one side or the other (or both), double-check with the manufacturer of the gasket. It didn't look like the old gasket had any goop on it (not that you could really 100% tell), and the head and block surfaces were totally clean when separated, so I concluded that no sealant was used before. So, I also did not use any.


I did, however, need to clean the block mating surface. Using a razor-blade, I scraped off every tiny anomaly. I verified that the surface was clean by running a new blade around the surface, holding it completely perpendicular to the surface. Any resistance or even a change in the sound lead me to something that needed to be removed. This takes a long time. You can't rush quality, and spending the time here will pay dividends later.

Head Meet Engine
With a heavy head in hand, I thought about how to get the head to line up without damaging the head gasket. I tried putting a chop-stick into one of the head bolt holes in the block, but that only sort of helped. It did help me get my bearings, but, ultimately, I pulled the stick out before the real attempt. I found that random hoses or other things kept getting in the way, so I had to remove a couple of things I had not removed for the head removal in order for me to get the head to set. Most memorable was the removal of another coolant hose and pipe that wrapped around the rear side from the driver side to the front passenger side.

With the impediments removed, I could ease the head onto the gasket/block. I set it down gently and wiggled it lightly to make sure it set squarely on the 2 pegs on the exhaust side. I checked 2 of the head bolt holes with a chopstick, and confirmed that the stick set all the way through to the block. Knowing the head was aligned, I set new bolts through the head-holes. I finger-tightened them, then torqued to 30 pounds, 40 pounds and finally 44 pounds. With my breaker bar, I did 2 1/4-turns (spec says 1/2 turn past 44 pounds). I put a little dribble of oil on the cam lobes and a little dribble into each spark plug hole. I replaced the vale cover gasket and installed the valve cover.

This post got super long, and the content creation has taken most of the last few months. Why? Well, remember how I'm slow? Yeah, someone says it will take 2-1/2 hours. For me, we double their number and increase it a measure, so 2-1/2 hours means 5 days for me. That's 5 full days, like 40 hours. If you spread that out across weekend days, it takes a long time. I know that sounds like hyperbole, but have you read this blog? Anyway, I'll post back on this soon.

Thanks, as always, for following along-