Cass seriously?? one day only to assemble a complete 3.8 engine?? How do we know it will run afterwards? I had the carbs rebuilt by the famous Joe Curto in NY. Still in the box they came. The machining has been completed. New everything. I think it would take 1 or 2 weeks no?

 

Talk of welding and brazing around old fuel tanks gives me a real shiver up my spine.
I know of accidents where old fuel tanks and drums have exploded even though they were emptied and washed out.
One included my father who was a trained welder.
Another was a friend cutting a hole in an old 44 IMP gallon drum with an oxy torch.
Apparently the heat will release old solvents out of the metal and they can then explode.
Just be very wary and seek expert advice before going down the welding/brazing route.

 

When my Dad worked on fuel tanks, no matter what they were, or what they used to be filled with, he would fill them with water.
At least that is what he did when he was teaching high-school mechanics.

 

It depends how many engines one has done.
When I did my first Junky sofa rebuild it took a number of days, after a while I could get it done in under 8 hours, that's including taking out near a 1000 staples by hand, rebuilding the frame, and suspension, and putting the whole lot back together again.

An engine is no different.

And about SU rebuilding, I believe this rebuilder to be a bit better.
I've compared his methods to Joe Curto's, and while Joe does a descend job, Rhys at Island Automotion's methods are a bit more refined.
Joe uses a drill press to line up the butter-fly bushings, while Rhys uses a lathe.

Island Automotion LTD (sucarburetors.com)

 

I replaced the one in my MK2 with a piece of copper pipe, it was a bit of a faff to get it in place but should resovle the issue. Once in I soldered it into place.

As mentioned in this thread I washed the tank out many times with water and then kept it full of water while I applied heat to it.

I welded in the repair plates, then soldered around them to seal them then applied a petrol tank sealant over this for good measure. I used a product called Slosh to prepare and seal the inside of the tank and i'm hoping that this has worked.

 

Thanks Homer.

 

Peter you are most welcome.

 

Wise advice. Be very careful degassing tanks. If my friend decides to repair his tank I will get help from our old safety officer who is a pro in the subject.
Fire extinguishers are another problem. A chap at our refinery had his head blown off by a rusty fire extinguisher that let go when he touched it.

Obviously our company extinguishers go through their annual inspection to safety code. Oil companies have to be safety fanatics.

 

Subject to all the safety requirements, it's fine to restore an old tank for most of our cars with SU carbs. However, from my experience with my series 3 Daimler, for a car with fuel injection, it's easier in the long run to buy new tanks. Injectors, high pressure pumps (and tank switchover valves) don't tolerate the smallest particle of rust.

 

Jose I assembled mine on an engine spit which meant I could rotate it around to do the bottom end then the top end. Only took a day as all the parts were there just needed to be assembled but you need to have the right tools to hand and the knowledge of what you are doing. Getting the engine into the car and connecting everything up took longer perhaps two days before we could turn the key. When we did turn the key we had a major gasket failure between the water pump and chain housing which meant with the engine in the car I had to strip everything back down, subframe out, sump off, radiator out, carbs off, exhaust headers off, cylinder heads off. That took another day to strip down and build back up. These things are sent to try us, so I have an intermate knowledge of my engine. One day to assemble the engine on a bench is reasonable. 8 to 10 hours.

 

Getting the valve shims set up correctly can be tedious, but once that is done and the head is ready to drop on, then I agree the engine could be assembled in a day. Absolutely, it has to be on an engine stand, than makes it so much easier.

 

Shimming the valves can be tedious and expensive but when I had my head machined with new valves and guides I got the machine shop to set all the shims for me. They had all the shims to hand so I only had to pay for what they used rather than buying a shim set (£350) and having loads left over.

 

The last head I did I have plenty of shims from various heads I've taken apart, so it was a matter of swapping them around and measuring. Then doing the calculations to see what shim I needed and I ordered just the shims I need. I probably had the cams in and out a half a dozen times though.

 

Two years ago I had a MK1 cylinder head rebuilt which involved extensive welding due to corrosion and new valve guides fitted. The valve inserts were refaced and new valves and valve springs fitted.
This was done by a reputable machine shop and the owner is a second generation engine builder. His father used to help me build up hotted up engines
When it came to setting the shims he advised me he no longer had a shim set.
However a friend and I had assembled a shim set over the years and I told him I could do the job.
He suggested I do the shim setting in his workshop under his supervision as he explained that way his warranty would be be sound.
I was setting up to do the 4 thou. inlet and 6 thou. exhaust clearances however he intervened and advised me that years ago they had decided that these clearances were too tight and had led to burnt valves.
He explained that valve clearances tended to close up one or two thou and in some cases even a bit more
He urged me to go to 6 thou. inlet and 8 thou exhaust which I did.
After I refitted the head and started the engine there was no indication of any excessive tappet noise and two years later it is still quiet.

 

That actually makes sense. You are likely to suffer some initial valve seat recession on a total head rebuild. You are probably close to spec after break in/run in.

(asperities on the valve seat from machining knocked flat by the valve thus closing all the gaps a little)

 

I had my engine machined, New valves and guides and the engine shop re shimmed the valves for me. I then assembled the engine myself and ran it for about two years before I noticed it was louder than it had been when it was rebuilt. The valves had slowly bedded in and the noise became slowly more noticeable. I took it in to another garage, Jaguar specialists, who shimmed the valves again for me. Not sure what they set the gaps at but would assume at 4 and 6 thou.The difference from what I thought was a slight tapping which had taken two years to become noticeable to after was pure engine silence. Only problem then was I could hear all the puffing of the exhaust joints which I had to seal up with band clamps. If it is not one thing it will be another.

 

My newly rebuilt engine sounds a little too quiet in the cam area for my liking ~ 4 and 6 thou. I will have all the gaps checked once fully run in. Fortunately my cams are still perfect profile. No little flats from lazy maintenance. Once you have flats on the cams they will always be noisy. They might have been replaced at some time. The engine had 90K miles on it. I've been playing with twin cam engines all my life starting with an Alfa Giulia Ti ~ my first car.

 

Shouldn't noise indicate too wide a gap? Is it possible they used some of the old shims?

I think the recommended 4 and 6 thou are aimed at ensuring a quiet valve train. Opening them up by 2 to 4 thou shouldn't cause any problems, apart from a very mild, but reassuring noise.

 

I like mind mine a little on the noisy side, I don't have to worry about burnt valves, especially on the exhaust.
I don't see any harm in having them too wide, the compression may be down a bit though, but I don't drive it hard anyway.
Not hearing any perceivable noise may indicate that there may not be enough clearance.

 

The only way the gap can increase with break in mileage & matters (tappets) become noisier after rebuild IMHO are that new buckets were fitted & have worn more during that break in than the valve seat recession which will close up the gap. Or as Peter says maybe bad shims.

The cams are tough as hell on these engines. The buckets not so much especially if they stop rotating.