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If you work on the components behind a dashboard, radio, heater core and controls and so on, you will adore this tool. The 1/4 inch driver and your sets of sockets as well as the screwdriver bits that come with the Chapman wrench are all big timesavers behind a dashboard.
If you have removed bumpers or mudflaps from late model vehicles, you know there’s a clearance problem between screws and tires. There’s no problem if you have one of these.
If you’re a pro, you probably own or want one of those tiny Snap-on 1/4 inch ratchet wrenches with a 2.5 inch handle. This Chapman wrench is much smaller, much cheaper and holds up well. I’ve used it on nuts and bolts up to 10 mm or 7/16 under the hood. I remember motor mounts with nuts that had to be broken loose with a 12 point box wrench before you could zip them out with a tiny wrench. Without a small wrench, you were finishing the job with the box wrench.
[url=http://www.mre-books.com/quadrajet/carbrebuild.html:1llxc7ms]http://www.mre-books.com/quadrajet/carbrebuild.html
H[/url]ere’s a page from the Cliff Ruggles book about the dreaded fuel bowl plugs on the Q-jet. On early Q-jets these always leaked when the carb needed a rebuild and mechanics (even some pros) would follow the instructions that came with the rebuild kit, ignore the plugs, and their rebuilt carb would leak and bog on acceleration.
It’s best to make a screw to fit the plug holes and seal it with epoxy. Use of taps and dies is a basic skill, even for a shade tree mechanic, and cheap taps and dies from harbor freight will hold up OK.
The 1986 Q-jet may not have leaky plugs or need throttle bushings. If you dip the parts in carb cleaner, you need to check for leaks after you dip them. I don’t check them, I just make the screws and seal them in.If you rebuild the Q-jet you have, you won’t need a new intake manifold. If you buy a new square bore carb (Holley or Edelbrock) the Edelbrock manifold at the top of the page is what you want.
It actually accepts both square bore and spread bore carbs and has clearance and bolt patterns for either one.
If you decide to rebuild the Q-jet, let me know and I’ll give you some more info.[url=http://www.summitracing.com/search/Department/Air-Fuel-Delivery/Part-Type/Intake-Manifolds-Carbureted/Make/OLDSMOBILE/?Ns=Rank%7cAsc:tyo283m4]http://www.summitracing.com/search/Department/Air-Fuel-Delivery/Part-Type/Intake-Manifolds-Carbureted/Make/OLDSMOBILE/?Ns=Rank%7cAsc
I[/url] used to buy stuff from Summit and their catalog was worth having. Order a catalog from them and you’ll have a better idea of what’s available.
Jegs is very popular nowadays. They both have websites.[url=http://www.cadvision.com/blanchas/54pontiac/qjet.html:20w85eb9]http://www.cadvision.com/blanchas/54pontiac/qjet.html
T[/url]his page has some good info about rebuilding Q-jets. He has experience with warped castings, probably common in carbs older than yours. He says he’ll pay a few bucks for used ones from the wrecking yard. This makes it possible to buy another Q-jet, rebuild it and use the car at the same time. That’s what I would do in your situation. Find the right carb, pay 5 or 10 bucks for it, and take your time rebuilding it. Re bush the throttle shaft if it’s loose, and always re-seal the 4 plugs under the fuel bowl with epoxy.
Buy the best kit you can find. It should come with a gasket that goes between the carb and manifold and it should have nylon bushings where the bolts pass through. This prevents warping the bottom of the carb.[url=http://www.ebay.com/itm/Holley-0-80555C-650CFM-Model-4175-Factory-Refurbished-/350517150199?pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr&hash=item519c7341f7#ht_2378wt_1163:2330o2s5]http://www.ebay.com/itm/Holley-0-80555C-650CFM-Model-4175-Factory-Refurbished-/350517150199?pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr&hash=item519c7341f7#ht_2378wt_1163
H[/url]ere’s a Holley spreadbore that bolts on the existing stock GM manifold. This is a new carb from Holley with a warranty, but it’s been returned so they sell them on E-Bay.
[url=http://www.spike.com/full-episodes/reh42f/powerblock-muscle-car-quadrajet-rebuild-season-4-ep-418:nt2h93eq]http://www.spike.com/full-episodes/reh42f/powerblock-muscle-car-quadrajet-rebuild-season-4-ep-418
C[/url]heck out this video on rebuilding the Q-jet. It begins by showing the difference between the square bore and spread bore 4 barrel carbs. The two have different bolts patterns and require different manifolds. I would recommend rebuilding the one you have over buying a Holley or AFB (Edelbrock). You say you plan to become professional so this would be good experience for you and an accomplishment too, because the shade tree fellows have so much difficulty with the Q-jet.
When I was first faced with your dilemma, I chose a Holley and an Edelbrock Performer intake manifold and that’s probably the most popular choice. Later I worked for a guy who rebuilt Q-jets (and engines) that ran perfectly. I had him show me the “tricks” and you can see them in this video. Subsequently, I rebuilt three Q-jets and all three ran fine. One of them was a late model “electronic Q-jet” or “hybrid Q-jet” like yours with the throttle position sensor and the control solenoid. You need a digital multi-meter (or DVOM) to adjust these.
If you can take your time and do this right, you’ll save money and acquire skill. Maybe you can’t afford to lose the use of your vehicle for a short time. If that’s a problem, the easy way to go is with the Edelbrock and a new manifold. The Holley and a new manifold is a close second. There is a Holley spread bore that bolts up to your manifold, but it costs more and it’s not popular. I have no experience with it, but I had one expert friend who claimed it beat square bore Holleys. (My policy is I don’t recommend anything unless i have direct experience.)
There used to be available an adaptor plate that would let you bolt a square bore onto a spread bore intake, but the square bore carb primaries are bigger than the corresponding primaries. Bad idea, but I think they used to sell a lot of those adaptors to guys that would use them for a while, then buy the new manifold and do it right.Thank you, John. I hear that Chevy has a 2 liter 4 cylinder with direct injection and turbo that makes almost 300 hp and it’s already available.
Sarah, Your car was built right around the time when Oldsmobiles came with either the Olds V8 as well as the Chevy V8. When Olds first started doing this, some buyers discovered Chevy engines under their hoods and claimed they had been misled and cheated.
Do you know which engine you have? You can go to Google images and enter “Chevy V8 ” 305 or 350. Or enter “Oldsmobile V8” 307 or 1986. The Chevy V8 is easy to spot because it has “ram’s horn” exhaust manifolds and exhaust ports that are not equidistant. I imagine you know this already, but I also remember that beginners get terrible advice from other beginners and tend to believe it when it comes from someone a few years older.
I’ve assembled Chevy and Olds V8s and I’ve replaced a Chevy V8 timing set without removing the engine. I think we can find a video that will show you how to do this.
There’s a special tool for R&R of the front balancer on the Chevy V8. You can buy or rent it but it’s very risky to shortcut the tool (been there, done that).
I’ll see if I can find a video for you. I’ll have a couple of suggestions for your carburetor question too.Thank you, Eric. I could hardly claim to be expert in GM, but I know a bit about old Chevy, Olds, and Pontiac engines. 1950 is the year I was born and I had some professional experience with Alfa Romeo twin cam engines with side draft Webers and mechanical fuel injection (1960s and early 70s cars).
My most valuable experience came from hours of watching professional mechanics work on imported cars mostly, so I am naturally very impressed with your videos. I learned from books, an auto shop class, pros who were willing to answer questions, and from trial and error, but watching was invaluable experience, and I know few of us were able to do much of that before the internet, and YouTube, and excellent videos like yours.
I overhauled several Alfa engines with modifications before attempting a V8, but those are all easy compared today’s engines.The Chevy small block V8 has a timing chain cover that seals against the oil pan, so there’s additional hassle when you replace the timing set with the engine in the car. You have drop the front of the oil pan down, something I wouldn’t recommend trying without watching a video first. The Olds engine doesn’t have this problem. There’s a tool for re-installing the front balancer on a Chevy small block. I don’t remember if the Olds uses the same tool or a similar one.
[url=http://blog.al.com/engine-block/2009/03/72%20engine.jpg:7lnefh0y]http://blog.al.com/engine-block/2009/03/72%20engine.jpg
S[/url]arah, Here’s a pic of a Chevy 307. Note the rusty ram’s horn exhaust manifold and it sits directly under the the red valve cover. The Olds V8 looks similar, but everything is more massive including the cylinder head, so the Olds exhaust manifold sits about an inch and half from the valve cover.
I think your engine must be an Olds 307.
You don’t need to post pics of your motor and long as you’re sure it’s not a Chevy small block.
You can look for videos on Google for “Oldsmobile V8 timing chain”. The size of the engine doesn’t matter as long as it’s Olds. There’s one about an Olds 455 that shows you what the chain looks like with the cover off.[url=http://www.youtube.com/watch?v=Ex_yJ_V5UH8&feature=related:10pt4rld]http://www.youtube.com/watch?v=Ex_yJ_V5UH8&feature=related
C[/url]heck out this video about re-installing a balancer with a special tool. This a Chevy V8 and he’s left the timing cover off so you get a better view.[url=http://www.youtube.com/watch?v=QORm5fnCvYA:32cw3dhe]http://www.youtube.com/watch?v=QORm5fnCvYA
H[/url]ere’s removal of the balancer. A Chevy V8 again but it’s the same operation on other engines.http://sdparts.com/category/moroso-harmonic-balancer-installer
Moroso has an installer for an Olds engine. You’d be better off renting one. You can rent or buy a puller. Even harbor freight would have an adequate puller.
I hear some Olds engines don’t need an installer and the balancer just slips on. It’s much harder to find someone with knowledge of old V8s than it is to find someone with knowledge of the Chevy small block.If your engine has the typical Quadrajet 4-barrel and the original intake manifold, you have a decision to make about the intake manifold. This presents an ignition timing problem because you have to pull the distributor if you change the intake manifold. The Holley and Edelbrock (AFB type”) carbs are square bore carbs and don’t bolt up to your GM intake manifold.
Holley makes a Quadrajet replacement 4-barrel carb that bolts up to the stock manifold. I had a knowledgable friend who swore by them, but it’s probably one of very few carb types I haven’t owned.
Your ignition timing has to be correct before you install a Holley, because you can break a Power Valve inside the Holley if it’s not. The newer Holleys have a feature that prevents this, but I’m told, it doesn’t always work. Anyway, your timing needs to be correct in any attempt to modify that engine.
I hope you are not planning to go Holley or Edelbrock to increase the size of the carb and this will not improve performance unless the entire engine is reconfigured.
I’m in California and we have to pass emissions tests that preclude using most aftermarket carburetors.
Why do want to change it? I can think of lots of good reasons you may have, but I might be able to make a recommendation if I knew your reason.