27 votes
Accepted

What should always be replaced when rebuilding an engine?

If the intent is strictly to rebuild, here is a list of items which should always be replaced: Rings Compression rings Oil control rings Bearings Main bearings Rod bearings Cam bearings (not ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
8 votes
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Should I replace piston rings on chevy 350?

With only 200 miles on the engine, I'm thinking you could get away with using the same rings on the engine as long as you didn't see any scoring on the cylinder walls or any other obvious damage. ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
7 votes
Accepted

When to bore a block during a rebuild?

I've nothing to cite for this, but I'd say the following: When should you bore a block during a rebuild? Only if necessary - if the bores are damaged, scored or heavily pitted. How do you determine ...
Nick C's user avatar
  • 28.7k
7 votes

What can be done about an underweight piston?

Typically when weight matching pistons, you do exactly what you're saying you don't want to do ... that being, you weigh all the pistons and use the lowest weighted one as your goal. Since you don't ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes
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Is this cylinder head junk?

This, in and of itself, is nothing to be worried about. The reason I say this is, it is not part of the sealing surface for a cylinder. There is more than enough meat there to seal the cooling port, ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes

Should I replace piston rings on chevy 350?

I would replace the piston rings and inspect the pistons for any signs of damage. You are already investing money in repairing the engine. It does not make sense to skip such an important part. Make ...
race fever's user avatar
  • 3,353
6 votes
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How to Remove Core Plugs? (aka Freeze Plugs)

This video confirmed what I was thinking. You need three things: Flat tip screwdriver Hammer Channel locks pliers (or ViceGrips) Take your screwdriver and hammer. Place the screwdriver flat along ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
5 votes

How to Remove Core Plugs? (aka Freeze Plugs)

Sometimes really corroded ones will not remove like that or there is a lip behind the core plug that doesn't allow that to happen. Sometimes you can drill a hole in it and screw in a bolt with a self ...
Newbie Noob's user avatar
  • 2,781
5 votes
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Transmission Rebuild or Replacement

In general, a transmission should last for the lifetime of the car, assuming regular maintenance (regular oil/filter change according the specification). On manual transmissions the clutch (and dual ...
Martin's user avatar
  • 8,448
5 votes
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Assembly lube for engine that has been sitting for years

As you suggested, absotutely use assembly lube on the parts you've taken apart and cleaned. This will ensure there's no wear there while the parts are waiting on oil pressure to build-up and lubricate ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes
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Using a thicker head gasket when the cylinder head resurface limit is reached

The pressure generated at Top Dead Center on the Power stroke is very high. A "taller" gasket will have a larger cross-sectional area exposed to this pressure, so high "pounds/sq inch" grows ...
SteveRacer's user avatar
  • 12.4k
4 votes
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How do I properly break in an engine after a rebuild

Piston ring breaking standard procedure involves how the engine is used for the first 500 miles. No extended idle time Easy low power driving with lots of changes of rpm No high power accelleration ...
Fred Wilson's user avatar
  • 11.6k
4 votes

General Order Of Engine Removal Steps

I'd generally go for the following, adjusted as appropriate for your car (as some things may be easier to get to in a different order) If the paintwork is in good condition, cover and protect the ...
Nick C's user avatar
  • 28.7k
4 votes

What should always be replaced when rebuilding an engine?

all parts should be washed and checked for cracking or fatigue The list of items you don't need to replace is much shorter: the block but you may need to get the deck resurfaced and you will need to ...
Cc Dd's user avatar
  • 2,879
4 votes
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Lapping valves by hand - does the compound have to be cleaned off?

Yes, remove all traces of the lapping compound - it is the metal to metal joint between the mating faces that is being tested.
Solar Mike's user avatar
  • 34.6k
4 votes

Should I be concerned about eccentric valve rotation?

The part you don't show on this exhaust valve which is much more important is how the lapping ring looks on the valve. If the ring which shows the lapping looks even all the way around on both the ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes
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This valve is pitted - what options do I have?

This valve can absolutely be salvaged. You just need a valve job. You can have a look at what's entailed in a valve job by watching this Jafromobile video. To the uninitiated, I won't go through all ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes

Lapping valves by hand - does the compound have to be cleaned off?

Not only should it be cleaned off, you want to ensure you don't get/leave any on the valve stems. You'll wear out the valve guide in short order if you don't. Remember in engine building, cleanliness ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes

Is there a hack to repairing a seized engine?

It will almost definitely be cheaper to buy a reconditioned engine and drop that in than trying to sort out a seized engine. This is because you're going to have to pay for a lot of machining work in ...
Captain Kenpachi's user avatar
4 votes
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Rebuilding EV1 Injectors

I had a similar worry when I replaced the pintle caps on a set of my own injectors. In my case I actually hadn't installed them far enough on to the injectors themselves and they were causing a weird ...
Techlord's user avatar
  • 643
3 votes

Lapping valves by hand - does the compound have to be cleaned off?

Yes it must absolutely cleaned off. The compound is an abrasive paste, as such on initial start up it will be ingested into the engine. The outcome would be the same as leaving some fine sand on the ...
mikes's user avatar
  • 19.9k
3 votes

On rebuilding an engine: can anyone define "free spinning the crankshaft"?

This is essentially looking for binding. It has nothing to do with how long it will spin on its own inertia. As you progress thru the assembly, it should turn with little effort to ensure there is no ...
CharlieRB's user avatar
  • 9,015
3 votes

How to store a just rebuild automatic transmission

welcome on this site. Good luck with rebuilding the transmission, this is one of the bigger challenges in car maintenance. You need to store the transmission with ATF inside in a clean dark place ...
Martin's user avatar
  • 8,448
3 votes

How do I properly break in an engine after a rebuild

I'll stick my neck out and fly against convention. There's a great article here: http://www.mototuneusa.com/break_in_secrets.htm I've verified this method with a number of motorcycle and race engine ...
RemarkLima's user avatar
3 votes
Accepted

Is there a hack to repairing a seized engine?

for a little background, I am a Kia master tech. Hyundai and Kia are brother sister companies who share mostly the same drive-train components. both companies have had issues with the 2.0 or 2.4 ...
Max's user avatar
  • 146
3 votes

Transmission Rebuild or Replacement

Yes and no, Auto boxes may need more frequent oil changes, but, properly looked after they can do 100K or 200K just as easily as a manual box. For a manual box the issue tends to be the clutch - as ...
Solar Mike's user avatar
  • 34.6k
3 votes

Should I re-build my engine?

No, you shouldn't rebuild the engine unless you have a specific reason. 120k miles isn't that much for a modern engine, so there's no reason to spend the effort, time and money to strip it down. Clean ...
GdD's user avatar
  • 16.9k
3 votes
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Overhauling EJ25 with arround 250k miles. Does it make sense to replace the main bearings and rings?

If you take the tact of "if it ain't broke don't fix it" then why would you rebuild it in the first place? If the bottom end is tight and you have minimal to no blow by, just put the head ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
3 votes

What can be done about an underweight piston?

I believe that, in general, if you're looking for this level of performance that a set of CUSTOM pistons is the usual solution. Alternatively, you could likely send this set to an engine builder to ...
jwh20's user avatar
  • 12.1k
2 votes

Should I replace piston rings on chevy 350?

If you are going to remove the pistons anyway, in order to fix the crank issue? Sure why not, because you are going to have to put rings in it when you reassemble. But, if they were replaced when it ...
CA Martin's user avatar
  • 121

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