Knocking In Engine

[4x4tillidie]

if there is anyone who can help me pleasee [-o<

my 86 bronco has a knocking sound coming from the front engine compartment i changed the spark plugs and the wires and the knocking got less and then when i changed the gritty oil the sound got even less noticable but it is still there and it seems to get louder after i drive then put it inot park

if anyone can help it would be greatly appreciated

 

[BigNasty]

Sounds like it may be time for a rebuild...

Knocking can come from a few things, some external and some internal but with the change in the noise after an oil change, I am willing to bet the rod bearings are on their last legs.

 

[broncoshell]

I would have to agree with bignasty. some 302 engines in early 80's >- had crankshaft problems & that could be it also but your still talking rebuild... What engine do you have & how many miles??? Good Luck

 

[stinger]

well i guess it is time to stuff a 460 under that hood!! $-) or just rebuild the motor you have.

 

[Ktomek06]

Im w/ them..time for a rebuild!

 

[Shadow_D]

I'm with everyone else on this one.

My 351 knocked bad when it was idling and I didn't have any oil pressure at idle or low RPM but it would go up and the knock would get less when @ higher RPM.

It also got less when I changed the oil.

The 351 is known for having problems with the main and rod bearings going bad with higher miles.

Now is the time to think about what you want to do.

Are you able to do the rebuild yourself? If so that will save you a lot of money and you open up a lot of options as to performance and other things.

 

[Seabronc]

Knocking can be as simple as the lifters being worn. Take off the valve covers and see if any of the lifter feel real loose. If so, they are not adjustable. The simple quick fix for this is to replace the worn lifters. Individual lifter arms can be purchased for about 35.00 a pair. If replacing loose lifter components only do the loose ones. If you want to get a little more ambitious get a whole kit. I personally wouldn't waste my money on a kit unless I was actually doing a rebuild.

Expect to see a gritty mess under the covers, something akin to oily dirt. You should plug the drain holes and spend some time cleaning this junk out, if this is all you need to do at the moment.

As far as oil pressure ic concerned, if you are using 10W30 go up to 10W40 or 10W50. These steps may give you some time while you get the stuff together for a rebuild.

Rebuild time can be shortened by buying a short or long block so you don't have to do the lower end stuff. A short block has all the bottom stuff done and you add the top end (heads, manafolds, intake stuff, carb or FI). With the long block, you get the heads. A long block can be purchased at Auto Zone for about $1,000.00 with your old engine core returned to them. The disadvantage here is that you don't get to select the components for the bottom end. Do a little research on the net to see what rebuild kiits are available. Visit a speed shop and talk to them about kits. The rebuild cost will vary widely depending on what you actually do to it. A 351 for example can be easily be pushed to 500 HP but don't expect 15 MPG /emoticons/[email protected] 2x" width="20" height="20" /> The more you push an engine the shorter the engine life is.

Like commented earlier, if you want to make a racing Bronco, stuff a 460 in it /emoticons/[email protected] 2x" width="20" height="20" />

Keep us posted.

Good luck,

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