The oil pan and oil filter were removed for inspection. I didn't find any parts, pieces or metal shavings in the bottom of the pan and that's good. I did find what looks like sludge though. We have a fresh built motor and fresh oil so the sludge makes no sense. I decided the only thing it can be is the zinc additive ZDDP. ZDDP is recommended for older engines to help lubricate the solid lifters and the cam. If you think the sludge is something else let me know.
Dennis K put me on to this neat product. It's a one piece pan gasket made by Fel-Pro. The pan gasket on a small block Chevy is usually four pieces that require silicone at all the joints. This gasket is installed dry, has inserts in all the bolt holes to prevent over torquing, and it should solve the oil leak we have near the bell housing.
It's hard to see, but the black area in the middle of the photograph is the underside of the birdcage. This area will never be seen by anyone because the frame rail covers it up. None the less, both sides were painted with Eastwood's Rust Encapsulator, a very durable chassis paint. It was tough to get at but it's done.
Remember this? It's the last rusted area we fixed on the bird cage. The metal was repaired but we never fixed the fiberglass floor.
To make the repair the duct-tape in the middle was used as a form. Fiberglass goes over the top of this duct tape. The ring of duct-tape along the bottom is used as a dam to collect excess resin. Between the two the fiberglass repair should be fine.
To understand this picture you have to remember that our resin is clear. Click on the picture and you'll see the duct-tape form is on the backside of the fiberglass repair.
Here it is a day later. Now all I have to do is remove the duct tape. Fiberglass does not stick to duct tape so the job should be simple.
It worked great. A little grinding here and there and the floor will be ready for Dynamat.
And finally, look what we have. Grey spoke American Racing Torque Thrust D's made in the USA. These are more "period correct" than the chrome wheels we currently have on the Corvette. I will put these grey wheels on the Corvette, then put the chrome wheels on our newly acquired Nomad, then sell those old Cragars that are currently on the Nomad. It's time the Cragars go and this is my method.
We have lost a very important part of this build. It's unfortunate and I am bummed about it. That will be the subject of our next post.
John. This is interesting. 2 minute lab summary read for you. Jim
ReplyDeleteStart-Up/Break-In
More than ever before, the procedure used when first starting a fresh engine and breaking in a new flat-tappet engine is critical. The best way to ensure there are no problems is to follow the cam manufacturer's (or engine supplier's) procedures to the letter. If you're building your own engine, use plenty of quality assembly lube on the cam and lifters; with any engine-homebuilt or crate-prime the oil pump, oil lines, and fill the oil filter with oil using an auxiliary pump, operating the internal oil pump with a hand drill or an external pressure tank. If the engine is equipped with stiff valve springs (more that 160/170 lbs of pressure seated, 290/300 open), lighter break-in springs may be necessary (check with the cam manufacturer on this one).
When the engine is first fired, use one of the break-in oil additives available (COMP Cams recommends its PN 159 with the company's 'shafts) and follow the cam manufacturer's/engine supplier's recommendations for run-in procedures. Generally that means running the engine at a fast idle for half an hour, shutting it down, and then re-torquing heads if necessary, checking valve lash and so on. Some engine builders will change oil and filter at that point; others prefer to run the oil and the break-in additives 500 miles before dumping it. We usually change the oil, then add another dose of break-in additive and run that for a few hundred miles. It's also advisable to keep idling time to a minimum until the engine is broken in; again, that's because the cam and lifters don't get much oil at low engine speeds.
Engine Oils
Although we were sworn to secrecy as to the source, a representative of one of the largest engine remanufacturing companies in the country admitted that they break in all their engines with diesel mineral oil. He offered two specific reasons for this. First was that the higher level of ZDDP offers increased protection to the cam and lifters, which was almost a given. The second will come as more of a surprise. They believe that because of the compounding, these oils are, in his words, "slightly less slippery," and promote spinning of flat tappets and biting of the rings to the cylinder walls, both of which help the break-in process. Although quite a few custom engine builders also agreed on diesel oil for break-in, others prefer racing oil and a few still rely on 30W non-detergent.
As we talked to various engine builders, we heard a variety of theories on the subject of oil for flat-tappet engines after the initial break-in period; diesel oil was a popular alternative. However, be aware that diesel oils have particularly high detergent levels. Those detergents "surround" deposits that accumulate in the oil and hold them in suspension, so much of it drains out when the oil is changed. However, these detergents will also stick to the inside of the engine and may result in sludge-like residue inside the engine.
Read more: http://www.streetrodderweb.com/tech/0803sr_modern_engine_oil/viewall.html#ixzz1nNKrtTrh
Jim, that is a great article.
ReplyDeleteWe have done most everything recommended in the article except using diesel. The zinc additive, break-in oil, 30 minute run-in at 2000-2500 RPM, etc were all done. Sounds like we had the same sludge the article discussed. Everything internal has since been cleaned, the pan has been re installed, and I re filled with Royal Purple Engine Break-In Oil, a synthetic oil with zinc and phosphorus additive for flat tappet engines. Royal Purple recommends this oil for the first 2500 miles on a new build.
I feel good that we have done everything right. I will not loose sleep over the sludge. Thanks for looking into this. Much appreciated.