Head-ache

[pdsman53]

Thanks for your help guys.

After the Head Bolt issue, I got a quote from a mobile guy called the Threadman...$300.

I called the guys that did my Head/Block machining at 'Peninsula Engine Reconditioners' and they said they could do it at a fraction of the the cost...$60 (and would do it on their way back from a picking an engine, the next day)....no brainer!! The last time I bought a Helicoil kit for 1x Bolt size, it was nearly $100 retail.
While they were here fixing the thread, we discussed re-using Headbolts and Head Gaskets...they suggested that I could re-use both, as I had only Torqued down the Head gasket and NOT Heat Cycled it. The Headbolts, I didn't want to throw another $280-300 at ARPs (my only option) and I had read numerous blogs where guys were re-using there original bolts...I put that to the guys from PER and they agreed that if they are not TTY, then they could be re-used...provided that they hadn't been stretched. I measured them, and decided to re-use them...Resprayed the Head gasket with Hylomar and bolted her up.
All good.

As I said earlier, I was a little worried about that initial startup...Spark/Fuel/Oil Pressure.
I'd also seen Videos from Engine Builders where they say "if you need to Crank any longer than about 30 seconds, you run the risk of destroying the Cylinder Bore Honing job that you just got done and may need to redo the Hone"....that's why I was a little concerned.

I did final checks that the CAS's were set, cycled the ignition 6 times, poured a little more oil down the plug holes, turned her over a number of times by hand (plugs out).
I was fairly certain that when I refitted the Oil Pump that I used a sufficient quantity of Vaseline, to help prime.
Just as an aside....when I removed the Oil Pump Bypass Spring and Piston, I noticed that the surface on the Piston was a slightly worn on one side where it passes the pump (it obviously doesn't 'rotate' during operation), so I just rotated it 180 deg and refitted it with Vaseline again.

I didn't realize Vaseline could be used for more than one purpose....maybe they should list the other options on the label.

So D-Day came...I had a 'smart' helper with me that I could rely on to check for leaks and any heat cycling issues.
Go!!
Crank, Crank, Crank....10seconds....and she fired up!!!
Obviously we had Spark, Fuel...and Oil Pressure was strong....success!!
Next worry....will she heat cycle properly....a few minutes later and the Demin Water level settled in the Radiator Funnel....success!!

Why was I worried???....(note to self "have a bit more confidence").

The Coolant Re-route kit from "Skidnation" saw the Temperature Gauge at the 'lowest' point I'd ever seen.

2x 20 min separate Run-in sessions on the Jack Stands between 2-3000 then 2.5-3000rpm, followed by 3x separate 1-1/2 hr sessions on the road gradually building to 5000rpm then using engine breaking back to 2000rpm and finally an hour of labouring up the tallest hill I could find in 4th gear.
3x changes of Mineral Oil 5w30 and Break-in additive and Oil filters later.

I decided it was time to do a Compression Test (using the same gauge).
Stone motherless cold engine....170/168/173/166 (I had oiled the threads earlier).
I'm pleased with the consistency, but was a little disappointed with the numbers, considering all the work....I was hoping to get to 180, with the new valve Springs/Valve machining/Tappet reset.
the Pre rebuild numbers were:
"I found that cylinders 2/3 (135/140 cold) are 25% down on cylinders 1/4 (170/180 cold)"
Great to see that 2/3 are back, but why are No's 1 and 4 lower than original??
I then remembered that when I did that test, I had taken the car for a run, let it cool down a little before doing the test....just so the Spark Plug threads didn't bind......so the test results weren't "apples v apples" (cold v warm).
A couple of other possibilities:-
....I cleaned up the Combustion Chamber "shrouding" on the outside of the Valve seats (better flow, but marginally less compression).
....the Cylinders had about 0.0025" Taper that the guys had to Hone out....so the new Rings end gaps, were toward the upper spec limit (blowby?).

I needed to do a "hot" test, just to confirm.

I had done a lot of Suspension setup work on our registered Trackday cars, over the last 6-8 years but the last time I rebuilt an engine was 40+ years ago (in 1980), it was a Datsun 180B SSS (novice) rally car....pre internet, with the aid of a Maintenance Manual.
Initially I wasn't totally confident that I should take on the task, but with the aid of the internet and other experienced guys who are willing to provide advice...it's not as onerous a task...if you have a computer, the right tools, the space, the time/patience, the money and the need/desire.

Looking forward to a Trackday....to see if all the engine rebuild and other work, hopefully finds us a few tenths.

Thanks again.
Jim

[PaulF]

Good on you Jim, I know the nervous feeling of cranking that engine over for the first time! Sounds like your hard work and attention to detail have paid off.