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Old 05-23-2008, 10:30 AM
rrgrassi's Avatar
mmmmmm Diesel...
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Originally Posted by P.E.Haiges View Post

To do the things the things Cervan suggests, U will have to take the rods to a machine shop. I doubt if U have the proper tools to do this yourself.

If I owned a machine shop I would have the tools. Kind of a no-brainer. Most work like that does require a machine shop.

70's SPM #5608 Fairmont A-4 MOW car

06 VW Jetta TDI 210K miles

03 VW Golf TDI 5 speed 372K Miles

RIP--Lost in fire...82 300D 322K was My Daily Driver-On the search for a w126 now...

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Old 05-23-2008, 01:49 PM
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Originally Posted by Cervan View Post
measure crankshaft with a mic. measure the conrod's (and check for straightness) and measure the main caps (the diameter) check for piston slap.
Cervan is right on the money. Bought an 83 Alfa Spider a number of years ago. The prior owner had done a restoration, with a new crank, pistons and bearings. After driving the car for about 100 miles, a bad knock developed. Sold it to me for a song, I inspected the lower block, and found one of the connecting rod bearings worn. The crank journal was fine, and I replaced that one connecting rod bearing. Sure enough, 100 miles later, the knock reappeared. Upon inspection, same connecting rod bearing was failing. Pulled the head, removed the offending connecting rod, and sent it to the shop. Shop reported back that the cap end of the rod was skewed, and not true when sitting on the crankshaft journal, which was causing the bearing to wear on one side. Remidial work was done to true up the rod, and the car was up and running with no further issues. The piston slap issue is one that can be louder when first started from cold, than it is when the engine is warmed up. Good luck!!
96 E300d
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Old 05-23-2008, 02:13 PM
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Location: Nova Scotia, Canada.
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I suspect you heard only one pronounced knock. That led you to the belief it would be easy to locate. That means to me at least the cause of that has to be found first. All rod bearings damaged just a little would not cause a pronounced knock in my opinion. More like a multiple drum beat if they all were really about equally damaged.
I would plastic gauge the rod bearings to try to find it there first. I believe it is usually the first or second rod bearing reported bad in situations like yours.
Did you take pressure off the individual cylinders prior to pulling the engine? Best method to isolate the knock first. Hope it turns out to be something not too hard or expensive to address. Also pry your crank back and forth and check the end play. Not likely the thrust bearing got chewed up but you never know. They can knock with too much end play.
Having only limited ability myself I might take my oil filter apart to check for a lot if any trapped metal. If none perhaps the bearings were already messed up from dirt over the years. I have taken apart engines years ago where the bearing surface had stuff driven into its surface. This scored the bearings prior to sticking in the babbit. Crank journals looked good. That does not mean they were not worn otherwise. Engines seemed quiet enough but were rebuilt because of excess oil usage.
The real full time working mechanics have got to offer better advice than a simple hobbyiest like myself. They probably have already.
I also continue to read all your threads by the way. Something has to be coming down the pike again at some point. I am patient and will wait though. It will be worth it.
Just to let you know you are not alone. I had to visit a home yesterday. They have a house only cat. I also knew that plus knew the woman was really attached to the cat. The six year old son screamed catch the cat about two seconds after I entered the house.
I saw a cat streak across the verranda and dissapear. I knew the lady of that house lived for her cat. . She was out as well.
After an hour of trying to catch the damm cat with maximum effort. The infuriating cat just sat under a shed and watched me. At this point the young fellow had a good look at him and told me it was not his mothers cat.
Sure enough I found her cat snoozing in her living room a few minutes later. All I could do was laugh and seriously consider death threat senarios for the young fellow.
I was thinking on the way home what I would tell the wife. She usually asks me what I did today and how did it go. I really did not want to tell her I spent part of it chasing pussy although I knew it would get a rise. Yet the devil made me do it anyways. I did get her totally undivided attention for an instant though.

Last edited by barry123400; 05-23-2008 at 03:09 PM.
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Old 05-24-2008, 01:36 AM
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Carrameow.. What happened to this rebuild?

aannnddd... is that the harbor freight 3-caster engine stand?? How does it fair for the 300 series diesel?

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Old 05-24-2008, 04:08 AM
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Originally Posted by jt20 View Post
Carrameow.. What happened to this rebuild?

aannnddd... is that the harbor freight 3-caster engine stand?? How does it fair for the 300 series diesel?
it will work, but it may require different bolts to hold the block (this will only hold the block, if you add the crank and head you may want to either reinforce it or buy a stronger one.) They seem to be flimsy but will work in a tight situation.. if your only going to use it once.. it doesnt matter.
Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?

As long as they would add one additional commandment for you to keep thy religion to thyself.
George Carlin (Wonder where he is now..)

1981 240d (engine donor 1983 240d) recently rebuilt engine hurray! - No more.. fought a tree and the tree won.

pearl black 1983 240d 4speed (Converted!@$$%) atleast the tranny was rebuilt.
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