Jump to content
HybridZ

[UPDATE] engine knock


Recommended Posts

Good news...I pulled the pan today and this is what i have found so far.

 

First the bad news;

 

1. The oil pump pickup was rolling in the bottom of the pan. Whoever built this engine didn't realize the importance of brazing the pickup to the pump

 

Now the good news;

 

1. No trash in the pan or filter!!!

2. The front main and rods 7 and 8 had no bearing damage (I ran out of time to check the rest).

3. I think the "knock" was either...

a. the loose pickup screen

b. the pump cavitating??

 

Everything was very easy to get to on these cars! I had the pan off in no more time then it took to put the car on a lift. (Mine is lowered so that took a little time...)

 

Since I have it opened up this far I picked up a new hi-pressure Melling pump, pickup (yes, I'll weld it on!!!) and steel intermediate pump shaft . I also purchased new Clevite rod and main bearings, pan gasket and rear main seal. No, I didn't forget the oil and filter smile.gif If I find any damage I'll report later.

 

More good news...the guy who sold me the car said it was just a plain old cast piston 350 (as far as he knew). I am happy to report spotting forged slugs hugging the cylinder walls! Oh, and last weekend I pulled a valve cover and was pleased to find roller rockers as well.

 

If all goes as planned I'll have her buttoned up by lunch tomorrow!

 

 

------------------

RickB@DragRacer.com

280V8

http://www.rickb.racemail.com

 

[This message has been edited by RickB (edited March 15, 2001).]

Link to comment
Share on other sites

That is good news.... think if you had kept driving it....look at one and two they are usually the first to go dry... good luck..

 

Just a thought....

I have had good and bad luck welding pickups.. If you get an aftermarket pickup they are thick enough usually to TIG no problem.. but on the stock pickups I have found that JB Weld works best. They tend to be to thin and when you weld them if you arn't careful the heat will weeken them enough to cause them to crack and break later on...Never braized one though..

 

------------------

Remember it is only a piece of metal.

Link to comment
Share on other sites

I can't remember where I saw it (Jegs, Summit, back of a mag) but some company has a bolt on bracket that holds the pickup from falling out. It might even keep it from rotating. Ought to be simple to make one.

 

------------------

Pete Paraska - 73 540Z - Marathon Z Project

pparaska@home.com

Pete's V8 Datsun 240Z Pages

Link to comment
Share on other sites

OK, this is the final lowdown...

 

#6 rod was knocking as the bearing was shot. All the others looked OK other than one other rod journal that wasn;t dressed well (on the chamfered oil hole).

 

All the main bearings looked good though I did replace them (with a little help from some friends!).

 

I also swapped in new rod bearings and cleaned up the two questionable journals with emory cloth. Of course she went back together with a new rear seal as well.

 

After about 8 hours (and one major chunk out of my left index finger, OUCH) today it lives again and is back home!!! No knocks.

 

BTW, responding to Pete's comment on the pickup tube bracket. PLEASE NOTE; I had one crack and break allowing the pickup tube to pop out and i was not as fortunate as this time. It hurt a nice 406" SB bad. I have used them since but...I also tacked the pickup tube along with the the bolt down bracket!

 

 

 

------------------

RickB@DragRacer.com

280V8

http://www.rickb.racemail.com

Link to comment
Share on other sites

Hmm...oil of the day was Castrol GTX 10w40. I never really have settled on a favorite.

 

I used to sear by Valvoline Racing as i unstand that it is an ashless oil??? Basically...I dunno what best confused.gif

 

BTW, I did put in a new oil pump and steel intermediate pump shaft too...I now have better oil pressure than before.

 

But my finger still hurts mad.gif

 

Though it wasn;t too hard on the wallet!!!

 

 

 

------------------

RickB@DragRacer.com

280V8

http://www.rickb.racemail.com

Link to comment
Share on other sites

Rick, as I've never had to do any bearing replacement I'd love to hear a lowdown on procedure you went thru to R&R your rod and main bearings? I wasn't aware you can do all that from underneath/motor still in/heads on etc. I've only popped off main caps to inspect bearings before. I assume you had to remove your crank and thus front cover as well? or can you lower crank slightly/angled to access all bearings and how does rod removal happen just for starters of what I'm wondering...bearings are only thing I've never done on an engine I guess let alone in the vehicle (that and freeze plugs).

 

thanks for any info

 

(I'd feel a lot better if I felt it was something doable myself.....I've ALWAYS panicked when I thought I might have a bearing problem)

 

------------------

Of all the things I've lost, I miss my mind the most.

Link to comment
Share on other sites

OK Ross I'll relive the pain for you smile.gif

I will go ahead and post this as a new thread for the rest of the HybridZ brethren.

 

The V8 Z makes it much easier as the only bolts I needed swivels for was the front two oil pan bolts and the front main cap (which makes it a little tough to get an accurate torque reading).

 

BTW, no you do not have to pull the crank out or even take the timing cover off...

 

1. Disconnect battery cables.

2. Pull starter loose (remove or bungee cord out of the way.)

3. Drain oil and remove pan and filter for inspection.

4. Remove oil pump.

5. I started at the back rods (7 & 8) by rotating the crankshaft so the rod caps are at the bottom. I pulled one cap at a time. Push the piston up into the bore so as to remove the bearing. Rotate new bearing into place however works best. A hard piece of flat plastic will help though I carefully used a long slender flat blade screwdriver (CAREFUL!). Pull the rod back against the crank and reinstall the cap with new bearing. Remember "tang to tang"...

 

NOTE: Use moly lube on bearing wear surfaces or I prefer trans gel. Inspect as required as you go and remove light scratches or burrs with a strip of emory cloth. When using the emory cloth rotate the crank frequently until you are worn out and then do it some more smile.gif this will insure a good 360 degree finish.

 

6. Repeat procedure until all rod bearings are replaced. I torqued both rods after each sequence (i.e. 7,8 then 5,6 etc.).

 

Now comes the fun part rolleyes.gif (the main bearings...

 

7. First I loosened all caps so the crank could "sag" a bit. Then I used a combination of the above mentioned screwdriver and a hard slender piece of plastic I borrowed from a trimmer (for working with glass) to rotate each bearing out. NOTE: Rotate the "tang" side of the bearing out first! You will be wise to get assitance at this point as one person can rotate the crank while the other pushes the beearing around and out.

 

The front and rear main can be a real pain! In all honesty after inspection I decided to leave the rear main in as the additional surfaces would have made that a real fight. It could be done though.

 

8. Torque all main caps to spec.

 

9. Replace oil pump and torque to spec.

 

10. Replace oil pan and filter.

 

11. Replace starter.

 

12. Fill with oil.

 

13. Connect battery cables and start engine.

 

14. Determine a moderate amount of break in time for the bearing surfaces and clean and bandage any wounds from the above mentioned procedure.

 

Hope this helps someone, it was my first time (hopefully the last too...!). I have access to lifts and plenty-o-tools as I have friends at a large dealership that are MOST helpful!!!

 

 

 

 

------------------

RickB@DragRacer.com

280V8

http://www.rickb.racemail.com

Link to comment
Share on other sites

Guest Anonymous

To remove the upper main bearing, get an aluminum rivet(s) and stick it in the oil hole in the crankshaft, then rotate the crank and the rivet head will push the bearing out.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...