what is "normal" valve tap?

[dieseldumb]

7.3L n/a e350

doghouse off the motor. new bb injectors and return lines.

hearing a loud valve tap at highway speeds. still there at idle and low rpm's but not as loud. coming from passenger side. put auto-rx in the oil but no significant change.

i know these are hydraulic lifters and can't be adjusted. just wondering what is a "normal" valve tap sound ( if one exists ) and at what point should i be concerned.

thanks.

 

[david85]

There is no normal valve as far as I know.

 

[93f250idi]

mine has 272k an has no valve noise or "tap"

 

[Pele]

How can you hear valve tap over the rest of the noise the diesel makes?

 

[DeepRoots]

you're looking in the wrong direction boss....

you just put in new injectors and now have a knock. One of your injectors is trash.
I've installed 4-5 sets of injectors and twice, brand new I had a bad injector.
I'd crack lines and figure out which one it is, if you have an old spare that is known good, try it out in the hole.... if not, swap the injector to the other side and see if the knock follows it.

Not saying you don't have a valve problem, but it seems ALOT more likely that the last thing changed caused this.

Drew

 

[Agnem]

X2. Unless your saying you replaced the injectors BECAUSE of the tap, trying to figure out what it is.

 

[HammerDown]

x3 on looking to a injector...I tested all my "new" ones and they showed fine. However, at times I'll get a injector tap that sounds like a bad lifter.

 

[creighta]

Where do you get you injectors tested prior to install? If one turns out bad would be good peace of mind to have the replacement ok'd.

 

[Knuckledragger]

Truck repair shops have the necessary equipment, also some of the posters here have testers at home and may be willing to help you out.

 

[dieseldumb]

injectors purchsed from from typ4 - BB's and pop-tested.

will crack each injector one at a time to see if it makes a difference. i am new to diesels so don't know the "sounds" they make when healthy or ill. will let you know.

 

[88beast]

a member on here trashed a set of those pretty well a bit back wont name names or wanything you can find the thread but lets say dirt was involved in the install
so did you clean everything and make sure not to bug it up

 

[dieseldumb]

yes, i read that thread. blew out the area(s) with brake fluid before removing. used anti-seize on install

can i just open the fuel line a bit to isolate the injector being tested? or does the injector need to be removed? seems the latter might be messy with regards to the return lines.

 

[dieseldumb]

found a loose injector - that quieted it down some. opened several others and may have found a bad one, but cannot tell for sure. will order several more just to have on hand and try another one.

my concern was that the lifters were worn or plugged.

glad to be a member of this site. thank-you.

 

[dieseldumb]

btw, good point, agnem, but i ain't that bright.

 

[gatorman21218]

Just an afterthought- If you run 3 or 4 qts low on oil you might hear some valve noise. Fill er up and it will quiet down