Guys - my original 289 engine in my 1966 Mustang has a pretty noticeable tapping, clicking sound. It is a 57 year old engine. Do I go with a rebuild/refurbishment of my 289? Or, buy a new 302 crate engine? It’s just a car for car shows, occasional Sunday drives. Summit Racing offers an ATK 302 crate engine, about $4,400. My mechanic hasn’t found an engine shop that has time to do a rebuild. 4 to 6 months out from even starting the work. But he estimates it may end up costing about the same as buying a crate. Tough decision. Any thoughts or experiences on this topic would be appreciated. Thx all.
289 rebuild or crate engine?
iwantapony
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Here's what I'd do if it were mine....
a) Warm engine cranking compression test, Fully charged battery, throttle blocked wide open. Acceptable range 130-170 psi, no more than 20 psi difference between highest and lowest cylinders.
a1) If acceptable readings can not be obtained, rebuild is indicated.
b) If compression test is acceptable, drain oil and remove oil pan. Inspect main and rod bearings for wear. If the wear is not relatively uniform over 2/3 or more of the surface (less wear near the parting lines) then check clearance with a PlastiGage.
b1) If wear is abnormal or clearance exceeds .0025" for mains or .0026" for connecting rods then a rebuild is indicated.
c) If bearings and bearing clearances are acceptable, remove valve covers and check lifter movement at the rocker arm with a dial indicator and compare to specification for the camshaft being used. For a stock 289 2v/4v camshaft you should have no less than .2253" lift on the intake valves and .2325" on the exhaust.
c1) If specification can not be obtained a rebuild is indicated. Also, check rockers, fulcrum balls and pushrods for damage and wear and if adequate lift is obtained, correct as needed.
d) Remove water pump, fuel pump and front cover and inspect timing chain and sprockets for wear.
d1) If timing chain slack is outside specification (0.5" total at mid-point on slack side of chain) replacement of the chain and sprockets is indicated.
e) If everything, so far, is acceptable, you should have found the source of your noise. If not, and you suspect it may be a noisy lifter, remove the intake manifold and lifters and check them for bleed-down. The acceptable bleed-down rate is no less than 5 and no more than 50 seconds to bleed down 1/16" under a 50 lb weight with a 5/16" ball placed in the lifter cup. There is a special tool to check these (yes, I have one....) that looks like THIS.
e1) If any lifters don't meet specification, disassemble, clean and re-test. If still unacceptable, replace. You must break-in the new lifter as if breaking in a new cam and lifters. If you see wear on the lifter feet and/or more than one lifter needs to be replaced you should consider replacing the camshaft and all lifters.
Okay, so assuming a rebuild is indicated I would remove the engine assembly and disassemble down to the "short block" (block with crank, rods and pistons still installed). I would bring this to a good machinist who will remove the cylinder ridge, remove the pistons with rods and crankshaft, measure the cylinder bores for size, eccentricity and taper and recommend an overbore size, and inspect and measure the crankshaft journals to determine if a polishing or grinding and polishing to underside is needed. You can also supply them with the cylinder heads if you wish to have them inspected for valve and valve seat wear, stem to guide clearance, pressure testing (Magnaflux if iron) for cracks, etc., and estimate repair.
Depending on the machinist estimates you can make a decision as to whether it makes sense to rebuild the existing engine or to replace it. One of the more common alternatives to a "crate engine" is replacement with a late-model 5.0 from a '97-1/2 & up Explorer/Mountaineer. Many of these engines have little wear and may need little or nothing in the way of major operations.... some might benefit from a new set of bearings but most won't need a thing. A new oil pump pick-up tube for front sump and the installation of your original 289's oil pan, front cover, valve covers, intake manifold and carburetor, exhaust manifold and a few other "conversion components" can have you back cruising for few bucks. This thread might be "enlightening". lol. Got my GT40P up and running in my 66
a) Warm engine cranking compression test, Fully charged battery, throttle blocked wide open. Acceptable range 130-170 psi, no more than 20 psi difference between highest and lowest cylinders.
a1) If acceptable readings can not be obtained, rebuild is indicated.
b) If compression test is acceptable, drain oil and remove oil pan. Inspect main and rod bearings for wear. If the wear is not relatively uniform over 2/3 or more of the surface (less wear near the parting lines) then check clearance with a PlastiGage.
b1) If wear is abnormal or clearance exceeds .0025" for mains or .0026" for connecting rods then a rebuild is indicated.
c) If bearings and bearing clearances are acceptable, remove valve covers and check lifter movement at the rocker arm with a dial indicator and compare to specification for the camshaft being used. For a stock 289 2v/4v camshaft you should have no less than .2253" lift on the intake valves and .2325" on the exhaust.
c1) If specification can not be obtained a rebuild is indicated. Also, check rockers, fulcrum balls and pushrods for damage and wear and if adequate lift is obtained, correct as needed.
d) Remove water pump, fuel pump and front cover and inspect timing chain and sprockets for wear.
d1) If timing chain slack is outside specification (0.5" total at mid-point on slack side of chain) replacement of the chain and sprockets is indicated.
e) If everything, so far, is acceptable, you should have found the source of your noise. If not, and you suspect it may be a noisy lifter, remove the intake manifold and lifters and check them for bleed-down. The acceptable bleed-down rate is no less than 5 and no more than 50 seconds to bleed down 1/16" under a 50 lb weight with a 5/16" ball placed in the lifter cup. There is a special tool to check these (yes, I have one....) that looks like THIS.
e1) If any lifters don't meet specification, disassemble, clean and re-test. If still unacceptable, replace. You must break-in the new lifter as if breaking in a new cam and lifters. If you see wear on the lifter feet and/or more than one lifter needs to be replaced you should consider replacing the camshaft and all lifters.
Okay, so assuming a rebuild is indicated I would remove the engine assembly and disassemble down to the "short block" (block with crank, rods and pistons still installed). I would bring this to a good machinist who will remove the cylinder ridge, remove the pistons with rods and crankshaft, measure the cylinder bores for size, eccentricity and taper and recommend an overbore size, and inspect and measure the crankshaft journals to determine if a polishing or grinding and polishing to underside is needed. You can also supply them with the cylinder heads if you wish to have them inspected for valve and valve seat wear, stem to guide clearance, pressure testing (Magnaflux if iron) for cracks, etc., and estimate repair.
Depending on the machinist estimates you can make a decision as to whether it makes sense to rebuild the existing engine or to replace it. One of the more common alternatives to a "crate engine" is replacement with a late-model 5.0 from a '97-1/2 & up Explorer/Mountaineer. Many of these engines have little wear and may need little or nothing in the way of major operations.... some might benefit from a new set of bearings but most won't need a thing. A new oil pump pick-up tube for front sump and the installation of your original 289's oil pan, front cover, valve covers, intake manifold and carburetor, exhaust manifold and a few other "conversion components" can have you back cruising for few bucks. This thread might be "enlightening". lol. Got my GT40P up and running in my 66
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You need to check on parts, machinist and labor rates... Even a "stock" rebuild where the engine is ready to drop in and fire up will be at least that.
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Huh? OEM-type ignition coil use a COPPER plug.
Unless somebody has messed with the valves, there's no reason to do a valve adjustment. In fact, you'll risk giving the lifters too MUCH preload which WILL lower compression where a bit of looseness will have almost no effect. Do the compression test first to establish the engines ability to pump air. Make sure the engine is warm, the battery is fully charged, and the throttle is blocked wide open. If the results come back consistently low, squirt a bit of engine oil into all cylinders and re-test. If the numbers improve significantly (like 20 psi) then you have poorly sealing rings. If the improvement is nil then you have leakage past the valve(s). If you have any cylinder that is more than 20 psi lower than the highest cylinder then there's no need to go further, a rebuild is indicated.
You can use the compression tester's "adapter hose" attached to an air compressor to charge the cylinder with air (watch out, it'll drive the piston down and spin the fan blades) and you'll be able to hear where it's leaking. From the carburetor indicates an intake valve(s) is not sealing properly. From the crankcase (oil filler cap) indicates rings are not sealing properly. From the exhaust pipe(s) indicates an exhaust valve(s) is not sealing properly.
Sure, you can to a "complete tune up" to an engine that is in poor condition and it will make it run a bit better..... for a while, but it's not going to correct an engine that is basically in poor shape.
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This depends on whether the wear dimensions of the block, rods, and crank are within "serviceable" dimensions. If the bores are out-of-round, tapered or exceed the maximum diameter specification then no amount of honing is going to suffice and the bores need to be machined oversize, if enough cylinder wall material remains.... if the final cylinder diameter is going to exceed 4.040" (or 4.060" with sonic checking wall thickness) then sleeving or block replacement is indicated. The same with connecting rod bearing bore diameter (or if you want to change rod fasteners)... if the rods aren't square, the bores are tapered or out-of-round, the rods need to be resized. Crankshaft journals have an acceptable specification before machining to an undersize is required.
There's nothing really wrong with a drill hone..... when properly used.... but not as a substitute for machining.
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