Does rebuilding have to include a machine shop?

Question

I bought a GM 4.3 v-6 from a junkyard. I got ripped off. I was about to drop the motor into my truck when my mechanic friend noticed bad leakage around the valve covers. We took it off to take a look at the gasket and....GASP!!!! it was disgusting. The oil was CAKED on there thick. It was BAKED on there. on the valve terrain.. (it was so bad I couldnt get a socket around the head bolts!)

He said it could be from not changing oil ever. (true?no?) I took the heads off and looked at the cylinder walls.. Everything looks fine. The ridge on the top of the cylinder wall is not really that bad.

ok... to the point. cant I just buy the master rebuild kit.. put it all back together and just hone the cylinder walls? Or is it absolutley important that I take it to the machine shop and have it....
crank checked
heads checked
Bored out
block magna fluxed.
he also added in having the heads re-done..

I am not building a performance engine.. I just need to get my wheels rolling to work.. I dont have a million dollars to spend at the machine shop... Im broke. How much this machine work gonna cost (approx)

thank you
-outta breath

Answer 1

Just replaced a 4.3l for a customers s-15. I took the intake off to replace the gasket and the donor engine looked just like yours...f*cking nasty. He was on a budget so I threw it together and tossed it in. It runs awsome and uses no oil. He's going to flush the motor a few times and run bardhal 1 in it... but needless to say I wouldn't worry about yours I think these engines just natually create a certain amount of build up. Don't spend any useless money on it...buy the block and head gasket kit, check for flatness clean well and re-assemble...most wreckers give you 90 days warranty anyway.

Answer 2

i have to respectfully disagree with you off the top. you buy a junkyard 4.3 and are upset that the valve covers are leaking and there is excessive gunk buildup in the top of the heads.



for starters, the 4.3 is a powerful and long lasting engine. i have known them to last over 300,000 miles without the first replacement of an internal engine component. if you have had the heads off and checked the walls, you know the walls are good and no ridge, i would clean up the heads, and have a machinist look at the heads only for excessive warpage, and slap her back together with head gaskets valve cover gaskets, new water pump and gaskets, and obviously some intake gaskets. have fun

Answer 3

I would believe that for someone wanting a good engine you should of gone and got yourself a rebuilt one with a warranty.You can get a long block that comes with heads or one without.And then all you have to do is put all your other stuff from the other engine onto the rebuilt.It saves time and money.Machine shops are expensive just to have the engine block machined,line bored and to have the cylinders trued out.It would cost almost the same as buying a rebuilt engine but give or take some dollars.

Answer 4

Hello, first of all, when you pull the crank out just look at the bearings on the crankshaft and the rod bearings. If they are scarred then you should have the crank ground. now if the cylinder walls just have a little ridge, you will be able to hone them, but you should use a micrometer to check the size of the wall, if it turns out ok, then you will be alright to hone the walls. looking at the head gaskets will also tell you the condition of the head and block surface. Now if you took everything to the machine shop to be checked out, it run you around 200$. Hope this helps you out.

Answer 5

It's not the head gasket but the cylinder head itself that needs to be machined. Which means you have to remove the valves and in the case of overhead cam engines, the camshaft. So you would be wise to at least partially rebuild the cylinder head. This has nothing to do with the lower part of the engine, which will remain the same old engine and thus not rebuilt at all.

Answer 6

this will cost u around 300 for u to bring it to a shop.the caked oil residue is from not only not changing the oil but because they have ran castroil instead of pensoil. castroil is very bad for clumping up and stoping up your heads vavle terain.ad if its realy as bad as u say u def. need to drop the oil pan n check the bearings an most important take out the oil pump u will have to cuz oil is most likly clumped up in it as well n that will blow ur motor cuz it wont put out enough oil pressure anyways u can luckly fix this on your own spray degreaser on all of the caked oil n it will help dramaticly 4 u im sorry u got ripped off n goodluck to u.

Answer 7

Best to have everything done, especially after hearing about the sludge. Never know how much abuse the engine has had, sounds like it was abused.

Answer 8

Machining is necessary only if you want it done right, have the car run well, and have along reliable life.

Answer 9

I would take that engine back and get a full refund and then find another one.