The 6 most complicated restoration steps

Hagerty

A restoration in and of itself is complicated. Taking an object that is in less than desirable condition and returning it to its original condition—or as close to it as possible—requires tons of skill and understanding for simple objects. The restoration of a nice hardwood dining table could take weeks to do properly and that is a dozen pieces of wood. Scale that up to an automobile with thousands of precision parts that all have to interact flawlessly and, yeah, restorations are complicated.

Even if you elect to pay a pro there are steps in a restoration that just cause us to grimace at the thought of the task. Could boil down to the cost, time, or complexity of what needs to happen, or it could just be that for reasons unknown you just don’t want to. No matter, here are six of the most complicated restoration steps.

Carburetor rebuilding and tuning

carb rebuilding Corvair Rochester
Kyle Smith

It’s oddly polarizing to say this one, but the fact of the matter is proper care and feeding of carburetors takes an understanding of how they work. Take a minute to talk to a person who doesn’t like carbs and it usually boils down to how finicky the small passages are to keep clean and understanding how one seemingly small change affects the rest of the system. It nearly requires a degree in physics and chemistry to fully grasp just how precision-cut chunks of metal can accurately meter the amount of fuel going into the engine across a range of conditions. In short, it’s complicated.

Cylinder head assembly

The pieces are bigger than carburetors, but assembling a cylinder head requires the same attention to detail and even more specialty tools. Assembling a head that lasts requires setting proper spring pressures and sealing, which involves careful machining, parts selection, and also tidy and careful assembly. Yes, it is possible to just slap one together but could and should are two different things.

Engine machine work

We actually talked about this topic yesterday with a video from Jim’s Machine Shop, Inc on the process to complete just two of the machining steps required to bring a five-decade-old engine block back to service-ready status. It is literally tons of tools that possess the power to save an engine and also could mangle the operator or workpiece in horrific ways if anything but a skilled operator is at the controls. The precision required is humbling and the consequences of getting it wrong are significant.

Differential gear setup

Similar to the cylinder heads, differentials are something that most home mechanics don’t do often and that leads to it being a bit of a struggle when you do need the skill. Getting the gear spacing set perfectly on most differentials requires an understanding of precise shimming and the proper reading of the pattern in the paint that shows how the gears are aligned and meshing. Davin makes it look a little easy in this video and it still takes him a whole hour to have everything sorted out, prepped, and ready to work. It’s almost never that easy in the real world and, on top of it, gear oil is likely the most foul-smelling substance you’ll encounter when working on a car.

Paint application

RU_82_20210510_TrailBuddy_Paint_and_Fork_thumb_NoLogo
Hagerty

Mixing ratios, application techniques, and expensive specific-use equipment all conspire to make a paint job difficult, and that is before you even talk about space or safety. The chemicals used in a paint job are a serious health concern and also can be a pain to dispose of after the fact. Even if you have all that knowledge and equipment there is still the process of preparing the object to be painted. Knowing which primer to use when, what the surface finish should be, how long to wait between coats, and how to get a truly flat surface that will have the desired finished look is hardly simple.

Automatic transmission rebuilding

In the hierarchy of things understood by most enthusiasts, the internals of an automatic transmission exists as witchcraft to many. Valve bodies with precise-size check balls and springs that need to be in the perfect place make carburetors appear to be a middle-school project if you are doing anything but disassembling and reassembling by the book. Even then it is easy to get confused or lost in the cryptic valve body that has a hundred passageways and none of them are clear and easy to see. Impossible? Hardly. Certainly complicated though.

 

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Comments

    I agree with this list BUT it glaringly missing the single most difficult part. Metal work, including rust repair and fabrication. That is a rare skillset that takes years to acquire.

    There’s a great Youtube channel Fitzee’s Fabrications. He shows a lot of tricks to make body work much easier and doable.

    Agree Fitzee is good channel, but if you are a beginner check out TC on you tube, and watch as he goes from beginner to gaining confidence in restoartions,

    Jerry Cogan is absolutely right. For 75% of all restorations the cost of rust repair, metal work and paint can and will most likely exceed the cost of all mechanicals. The only exception could be the more mechanically complication cars like a Ferrari. I’m doing a bare metal restoration of a 1973 914 Porsche. The metal / paint work has exceeded the cost of a rebuilt motor, rebuilt transaxle, the complete brake system and all new suspension. That’s even after I stripped the 914 to a bare shell and mounted it on a rotisserie. American muscle cars I have done in the past have been a similar experience.
    If I could mention one other issue most people do not plan for. This problem is if you don’t have all the right parts or rebuilt assemblies on hand, at the correct time in a restoration, the project timeline will slip and that will always cost you more money. Once a restoration shop or an engine builder puts your project on hold it is very hard to get back in the queue. Getting back in queue always has a cost associated with it.

    You are absolutely correct. Rust repair is the killer of many restoration projects for many reasons.
    1/ It’s usually hidden. You don’t see it till you start to take things apart.
    2/ It requires expertise in metal fabricating, welding, body molding.
    3/ It requires expensive to own and operate equipment.
    Rust can end a restoration in it’s tracks and in the worst case send the whole project to the scrap yard. Can you tell that I’m from Ontario Canada?

    Years ago we had what we called the $7 carb rebuild kit that cost $42. We would buy the $7 kit, try like hell to rebuild a carb, fail and then buy a rebuilt for $35; hence the $42 cost…

    Mine is in the middle of the car, replaced it once and it wasn’t too bad of a fix. See “1965 Corvair GTP parts 1-8” on YouTube.

    I would think mechanical restoration is easier than body work, trim restoration and anything under the dash!!

    I would but at 68 YEARS Old, 6’2″ 240 lbs., it’s tough to get…. OUT FROM UNDER THE DASH of a 65 Oldsmobile 442 ONCE YOUR STUCK BETWEEN THE SEAT, DASH & CONSOLE !!…BTW…Took me 8 strong hours, over two days, to replace the $140.00 Radiator and $235.00 Condenser coil in my Mazda 6 sedan… worst job I ever undertook. Almost the same as a Ford Probe

    What I am noticing now is the increased cost of parts for the repair and restoration but even more so now is that all those little speciality mom and pop shops that have been in business for years doing upholstery, transmissions, engine work, body work, etc are starting to close up. These are places that I frequented for years that could custom bend an exhaust, make an old headliner look new. Heck there was a guy that worked at Aamco that used to build tricked out transmissions in his basement. I think this is the biggest problem now for those of us in process of repair and restoration of our beloved vehicles.

    John you nailed it, that’s the biggest issue (next to supply), and it stretch far into the trades …
    Yes you can be a doit-yourselfer but eventually we’ll all require someones assistance.
    I’m an electric motor re-builder, in the process of retirement to find time to work on my cars, yet I keep hearing … what are we to do? So there’s the dilemma!!!
    I’ll be around to help out, but I’ll be putting my life & time first!
    Thankfully for myself, I’ve pretty-much done it all, except upholstery =p somethings better than others …
    So what’s the answer? I don’t have it. In fact I think it’s a topic of contention on it’s own!
    Cheers, Mark

    The hardest thing about car restoration is finding someone to do the work that you can’t do that is QUALIFIED and DOES A GOOD JOB! Many hacks out there taking your good money and giving you crap back. Learn as much as you can and do as much as you can.

    This is highly subjective. Machine work, engine building, setting up differentials, etc. are all common to me but I can’t/won’t do body or interior work, or wiring. And then there are others whose skills are the opposite of mine. It’s best to buddy up with someone so, between you, you have all bases covered. THAT would make the ideal neighbor….

    Seat upolstery is my nemesis. Getting it right involves tools I don’t own and hand strength I do not have. 😩

    Yeah tried replacing my own seat covers using factory replacements; looked horrible; In a true upholstery shop; 15 minutes worth of time, he pulled here, pulled there without even removing my new covers…..and they were perfect!——- EXPERIENCE!

    Rebuilding carbs is easy. Get the right rebuild kit and watch a YouTube video. I think what the article is pointing out is things to leave to a shop, rather than things that are complicated. Bodywork is not complicated, just take your time. But other things require specialized tools and knowledge that the home mechanic cannot do.

    I think one of them is sheet metal repair, replacement, and refinishing. Takes skill and craftsmanship. All that engine and drivetrain stuff requires a repair manual and half a brain.

    Machine work, unless you can afford the equipment and know how to use it, let your machinist do it. Carburetors and Automatic trans are not that difficult. Painting takes some skill but be patient and read up a bit and you can do it. Gear setup – you can do it, but I still pay someone, it’s too important.

    Always balance out the ability to sell them when done or rent them for the job. I built a second story porch on my house some years back. After checking scaffolding rental costs, I bought some. When I was done, I put the stuff on Craig’s List. It sold for about 90% of the purchase price, which was much cheaper than renting it for a year. On the flip side, I still own an expandable reamer I bought for a job on my ’40 Ford and will never use again.

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