1962 Bentley S2
Ypsilanti, Michigan

Part III - Top End Overhaul

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March 22, 2010

I avoided doing this on Friday but today, Dave C. and I removed the leaking brake pipe that runs from the master cylinder area amidships to the rear axle. It's six or seven feet long.

I fashioned a new one with fresh Bundy tube and proper double flares. We had it in by lunch.

We purchased yet more brake fluid at the Auto Value store on Park St. at lunch and had her bled in short order. Did a bit of a test drive and the brakes feel great.

Pete Kohnken noticed one of the boot lid latches was not working correctly when he bopped by on Friday afternoon.

So while I was working on my double flares, Dave removed, repaired and replaced the right hand frozen boot latch and thoroughly lubricated the left one.

 

March 23, 2010

Based on yesterday's test drive, Dave wasn't 100% thrilled with the way the carbs were set or the way the choke was coming off, so he did some tweaking having reread the relevant service manual section. Now things are as right as rain, or as right as they can be with that pesky A4 cylinder not firing.

Also, the drive shaft needs to be gone through front to back, it rumbles pretty mightily at certain critical speeds.

Avoiding the inevitable compression test until after lunch, I busied myself cleaning the washer bottle assembly.

Dave H. joined Dave C. and I for lunch at La Fiesta Mexicana. Michelle apologized because they were using the type of avocados that oxidize rapidly. We were darned hungry and ate the guacamole too fast for any discoloration to occur.

Upon our return to the garage, we changed the engine oil and filter switching over to 15W-40. Nothing untoward was found in the old oil or filter.

After verifying excellent spark at cylinder A4, we hooked up Mike's really nice Matco compression tester. Absolutely NOTHING. Still nothing with a squirt of oil in the cylinder. Probably a valve then.

After removing the A-side valve cover, Dave H. noticed the A4 inlet valve pushrod was missing. That definitely fits our list of symptoms!

We found it down in the tappet chest using Mike's even cooler Snap-on borescope...

... and fished half of it out through the pushrod hole with a magnet.

It is bent and fractured. Although we tested all the valves carefully prior to starting the engine, the A4 inlet valve is now stubbornly closed even when coerced with hammer and drift.

Crap.

Not good news but certainly better than broken piston rings.

We can see the other end of the pushrod resting down near the (presumably collapsed) lifter but there's no sense trying to fish it out.

The preliminary thinking is that we will remove the carb assembly and lower intake to retrieve the pushrod piece and replace the lifter and examine the camshaft lobe for damage.

Then, since we're in the neighborhood, we'll pull both cylinder heads, disassemble them and overhaul as necessary: perhaps recut seats, replace valve guides, valve seals, etc.

March 24, 2010

I did not get much done this morning on the car front today other than pricing pushrods, lifters and top end gasket kits.

Dave C. removed the carburetor and choke assembly in its entirety.

I did however, finish building Mike Reszka's Restoration website. He's the guy with all of the cool expensive tools in my garage and does some pretty impressive work. Click here to check out some of his recent restorations.

Dave Hollister and Pete Kohnken came by followed by Bob Cowley in his Hooper-bodied 1956 Rolls-Royce Silver Cloud so we all piled in and drove it to lunch. The weather cooperated and we ate outside at the Sidetrack.

You'll notice Bob's number plate is missing: one of the cast letters became a bit loose, so Dave H. and Bob spent the afternoon engineering a seamless repair worthy of royalty.

March 26, 2010

I came in today and was delighted to see a half gallon of Ketel One Vodka sitting inside the Bentley.

Turns out Mike is really pumped about his new website put together by yours truly. Here's another link to it: reszkarestoration.com

Dave C. and I removed the lower intake and the tappet chest order in short order allowing me to remove the A4 intake lifter (the one associated with the broken pushrod) and see if it's okay.

We tested it in the hydraulic press with a fixture that Mike had. It seems to be stuck.

 

Here's a close-up of that tappet.
I fished out the lower piece of the pushrod (left of the arrow) which was resting in safe spot within the tappet chest. Very unlikely it caused any collateral damage.

Dave H. and Pete K. stopped by for lunch again today and came back to help out at the garage.

We also bumped into Frank Markus from Motor Trend Magazine. Frank came by to check our progress as well.

Dave fashioned a pushrod holder from a scrap piece of 2x8 to hold all of the pushrods in order of installation. We then proceeded to remove the rocker assemblies and said pushrods.

Other than the broken one, I rolled the other fifteen pushrods on a surface plate. They're all nice and straight.

The camshaft appears to be in good shape albeit a bit varnished including the lobe used by A4 intake. The tappet chest is a bit gunky but that's just a problem for the neat freaks rather than an actual issue.

Monday we will commence with head removal to see what's going on with that sticking intake valve.

March 29, 2010

Dave Cunningham and I spent the day removing items that are attached to or block removal of the cylinder heads.

The Hoburn Eaton power steering pump came out rather easily.

Prior to removing the York (?) air conditioning compressor I removed the refrigerant from the system. Believe it or not there was a significant amount still in the system.

Dave C. immediately set about cleaning and repainting the rather rough hewn compressor bracket.

One of the good things about our little pushrod setback is that the engine will be significantly cleaner by the time we are through.

I also disconnected the fuel line and heater hose connections on the back of the A-side cylinder head and the ignition wire brackets from the rear of both heads.

We will address the exhaust system tomorrow morning and then we should be ready to take the heads out.

Dave Hollister joined us after our lunch at Aubree's in Depot Town. He got the assignment to check the wear on the rocker arm assemblies.

To put it in a nutshell, there wasn't any wear.

The clearance between each rocker and shaft should be 0.0010-0.0015 inches from the factory with 0.0035 permissible in a worn engine. (Note that the factory spec on later S2 engines is 0.0010-0.00125.)

The worst clearance on both assemblies was 0.0016 and that was in one location. For all intents and purposes, this assembly could be sold as new.

March 30, 2010

The right (A-side) manifold came out without excessive coercion. Once Dave C. noticed the right side downpipe is fastened to the frame crossmember under the sump and removed the screw, there was plenty of play in the system. A few of the exhaust studs came out of heads along with their nuts but no harm was done.

Initial inspection of the combustion side yielded no ugly surprises. Cylinder A4 is obviously dark because no combustion was taking place, it's a bit oily from all of the priming we did a few months back.

If anything, the other three cylinders may be running slightly lean.

The photograph makes the cylinders and pistons look a bit crusty but rest assured, all is in fine fettle.
Without further ado, all of the valves and valve springs were removed from the head.
The frozen valve (A4 intake) had to be knocked out with a drift. It was very rusty.

It appears that all of the valve guides had been sleeved with bronze helical inserts as part of a valve job.

All of the valve stems, intake and exhaust are completely within specification but it appears that the exhaust guides are shot. The intake guides are marginal.

You can see the bronze insert in this exhaust valve guide.

The intake guides also had Crane umbrella seals installed.

Bearing in mind we've only looked at one cylinder head, it appears all of the valves with the exception of the A4 intake can be reused if they are re-faced. Same with the valve seat inserts, there's no visible recession but they need to be re-faced.

In a way, I am glad the pushrod bent because I would have had to remove the heads in the future. Uncorrected, the motor would most definitely consume oil at a very high rate.

March 31, 2010

Today, Dave H. and I removed the second cylinder head.

Dave immediately set about removing the valves and springs.

April 1, 2010

My morning was spent cleaning up the area for the cars and coffee open house this coming Saturday. (Don't forget!)

Dave C. worked on prepping the lower intake to be painted. Let's face it, he's been itching to do that all along.

Looking a bit vacant in the engine compartment...

 

Speaking of cars and coffee, Mike brought this prewar BMW over from RM so that folks can check it out on Saturday. Don't see these very often.

Note: the oil slick underneath is from the hot rod previously parked in that spot.

April 2, 2010

I washed t he cylinder heads to make them easier to transport. The valves were wire wheeled to remove carbon and/or lead deposits. It seemed like the A4 exhaust valve had the least amount of lead on it. This could mean that the pushrod for the A4 intake failed prior to the phase-out of tetraethyl lead in the mid-Eighties. The previous owner probably did not notice, it's fairly hard to feel the engine firing on 7 of 8 cylinders: it's designed that way. We used an IR thermometer to read the temps at each exhaust port.

Roy, Pete and I had lunch today which has fast become a Friday tradition. The weather has been fantastic all week. The high today was 80 degrees.

Roy brought his 1934
3-1/2L Bentley.

Pete brought his 1957 Silver Cloud.

I transported the Bentley heads to Dexter Manufacturing this afternoon in my '73 Silver Shadow. After an initial look, Chance agreed that the seats and valves need only be re-surfaced. He will have to take a closer look to figure out if the guides can have a second set of inserts installed. At face value, he liked the idea of using Viton Enginetech stem seals which are the favored choice (unofficially) in the RROC. Crewe also recommends converting the older V8s to a modern seal arrangement, but their seals are fantastically expensive and not as good as the alternatives.

April 3, 2010

Today's cars and coffee at the garage was a bit of a blockbluster.

This Alfa-Romeo 2600 was quite interesting.

And when's the last time you saw one of these?

April 5, 2010

After mixed results using an Earth-friendly paint stripper on the lower intake manifold, Dave C. changed gears and prepped the cylinder head of the '39 Wraith for painting.

Looks pretty good. Dave's off tomorrow. Plan is to put it back on the Wraith Wednesday.

Meanwhile, I spent the entire day installing the new parking brake cable. The good news is that it does not really matter where you start, all of the mounting locations allow you to slip the cable in sideways rather than thread it through, the only exception is the firewall. I started in the engine compartment, moved on to the passenger compartment and finished up under the car.

Since the old cable was cut and unuseable this definitely qualifies as forward progress.

April 6, 2010

I ordered a bunch of S2 cylinder head-related stuff from Greg Albers at Bentley Zionsville this morning. They had a NOS lifter and intake valve in stock.

I attached the intake and exhaust manifolds to the (Wraith) cylinder head along with a set of new gaskets. I finally got to use the set of brass exhaust manifold nuts that Bob Archambault made for me over a year ago, plus I touched up a bare strip along the bottom edge of the head with engine enamel. Tomorrow Dave C. and I will put the head back on the engine.

April 7, 2010

Pulled the Wraith out into the middle of the garage rather than bring all the British Standard Fine tools back to it.

I sprayed a layer of Permatex Copper Spray-A-Gasket on each side of the new head gasket (not shown) while Dave C. prepped the block for receiving the new head gasket and head.

I installed new tappet chest gaskets and installed the 24 2BA nuts and lock washers.

It took four guys, but we managed to lower the head in place without damaging its new paint job. I installed the 30 nuts and torqued them to 51 in-lb. After letting the head settle overnight I'll bring the nuts up in stages to a final torque of 231 in-lb.

As you can see, we've got the ignition harness and carburetor partially installed. Also hooked up some but not all of the coolant connections.

April 8, 2010

Flying solo today, I torqued down the head, attached the rocker assembly, tightened the remainder of the coolant and fuel connections and hooked up the ignition and exhaust downpipe.

The engine started easily but the top end tick remains despite a complete overhaul of the cylinder head. %#&*! The only possibility left is to rebush the rocker assy. After that, I'll just run it until it gets worse because everything else and I mean EVERYTHING else checks out.

April 9, 2010

One more possibility: one of the pushrod is tuliped at the top, it may also have developed a non-spherical cup shape.

I am headed south tomorrow morning on the RROC National Spring Tour and won't be back until the 20th. Not a bad way to kill time waiting for the S2 cylinder heads to come back. There will be a travel diary of sorts — click here. Dave reinstalled the air cleaner assembly that he refurbished and I installed the radiator fan. And at that, we called it a day.

May 8, 2010

I've been out of circulation for a few weeks working very long days at Michigan International Speedway in the NASCAR garages on the Shakedown event for the Progressive Automotive X Prize.

There were 30+ very excellent entries, most of them will return for the Knockout competition in mid-June.

Work on the S2 (and Wraith and Silver Shadow) will resume Monday.

May 10-11, 2010

Dave C. primed and painted the lower intake manifold.

I worked on removing, cleaning and replacing the little castings that hold the hydraulic lifters in place. Also installed the NOS lifter on A4 intake. You will recall that the old lifter may be damaged since it's associated valve seized.
Having run out of Bentley tasks while waiting for the heads to come back, I moved on to replacing the windshield seal in the Wraith. Turns out the new one was way too fat in cross-section and would not fit. I may have to get one made. I made this image to discuss the situation with a supplier of rubber extrusions in California.

May 12, 2010

The fuel pump on the Silver Shadow was making noises like it was on its way out. Took me all morning to remove it since I had to do it in my driveway. Didn't want to risk a trip to the garage in Ypsi.

Note my homemade lifting bar used in conjunction with the floor jack. Quicker and easier than breaking out the screw jack that comes with the car.

The Silver Shadow pump is very similar to the pump on the Bentley and will in fact neatly use up all of the purchased parts that weren't used on the S2 pump.

The diaphragms look pretty horrific. It does not appear that they were leaking but somehow the pumping efficiency was impaired. At least one side was ticking rapidly even with the engine off.

 

There was a little bit of crud in the valve body on the one side. This may have caused a leaky valve.

At any rate, I plan to replace both diaphragms and all four valves. The points (not shown) appear well-worn as well.

May 13, 2010

Dave set to work on the fuel pump today. The points weren't burned out but were 99% used up. No complaints: I have owned the Shadow for almost 8 yrs. accumulating almost 24,000 miles plus the pump was not new when I bought the car.

May 14, 2010

I spent the morning cleaning the Bentley's block while the heads are out. Doesn't look like much but it's better than it was.

I'll do a final clean on Monday.

A second hand report from the machine shop sounds promising: work on the cylinder heads is finally underway.

Dave got about as far as he could get today on the pump until new points and other random tidbits arrive next week from Burlen Fuel Systems.

Peter Pleitner came by in his 1948 MG TC — very nice. Pete Kohnken also dropped by in his 1957 Silver Cloud.

The whole crew then went off to Powell's Pub for the Friday shrimp special including Paul and Scott from 203 Custom Car Works. Turns out there was only enough shrimp for five of us so Paul, Scott and I had burgers instead.

I paired my burger with fried mac and cheese wedges and three pints of Pabst Blue Ribbon. This led to a precipitous decline in afternoon productivity.

May 17-21, 2010

Still waiting for parts, so I did some additional wind screen seal research. Thanks to Todd, I found an exact match in the Baines Rubber Extrusions and Mouldings Catalogue (UK). In an email note riddled with condescension, the account representative informed me that the minimum order is 350 meters. Whatever.

I contacted John at Karr Rubber in California. They have agreed to create a custom die based on the sample I sent and should have 50 ft. of the stuff for me in a few weeks.

Dave H. suggested I remove the carbon from the piston tops of the Bentley since I had the heads off anyway. I bought a stainless steel brush for my die grinder to assist in this endeavor.
Here's piston B1 half done. Note it is stamped "B1" at 10 o'clock.


photo credit: Garry Campbell

May 22-25, 2010

Garry and I took a quick trip to Manitou Springs, Colorado at the behest of out our dear friend Ken. He moved to this picturesque village in the shadow of Pike's Peak from Detroit about five years ago.

photo credit: Garry Campbell One of the first orders of business was to take the Pike's Peak Cog Railway. The two car articulated train has four 850 cid Cummins turbodiesels driving cogs that lock into the toothed third center rail. On this 8.9 mile route, the train hits grades upwards of 30%.
photo credit: Garry Campbell We made it above the tree line to approximately 11,000 ft. but were forced to retreat at that point due to 90 mph gusts on the peak.
photo credit: Garry Campbell

On the way into Colorado Springs for lunch at Lau's Tacos one passes the Garden of the Gods. This is a city park of incredible beauty and oddly enough, it's free.

Not a bad way to spend a long weekend! Thanks, Ken, for everything!

In the meantime, the Silver Shadow fuel pump parts have arrived at the shop and the cylinder heads for the Bentley are complete and will be delivered on the 27th.

May 27, 2010

Dave C. set to work on overhauling the Silver Shadow fuel pump.

Meanwhile Dexter Mfg. delivered the Bentley heads to the shop. This is the combustion side of the A-bank. You can see the shiny new A4 intake valve second from the right.

All of the guides have been sleeved and reamed with new Enginetech seals on the intakes, plus all seats and valves have been re-faced.

May 28, 2010

I set about installing the Silver Shadow pump back at the house. It's not the easiest thing in the world to do when you do not have a lift available. What's worse: the pump still exhibits the same slow tick (rather than no tick) behavior after the float bowls have filled. I don't regret overhauling the pump as it was on it's last legs. The next suspect is leaking float needle(s).

June 3, 2010

The machine shop cleaning process on the Bentley pretty much removed what was left of the paint. Here I have repainted them with semi-gloss black POR-15.

Here's the A-head dressed with gaskets, spark plugs and most of the blanking plates and brackets.
The new head gaskets use modern materials. They apply to all Rolls-Royce and Bentley V8's 1959-2000. Nothing need be smeared or sprayed on.

June 4-5, 2010

Here you can see both heads in place. The exhaust manifolds are installed and connected to the down pipes. A-bank is torqued to 40 ft-lb., B-bank is still only finger tight. It's pretty cramped in the engine bay and it seems each of the 20 head nuts requires a different combination of extensions. Slow work.

The monthly open house for the garage is tomorrow, I also set lower intake manifold in place "for show".

Another week or so and it should start looking like a complete engine!

June 7, 2010

After torqueing the B-bank to 40 lb-ft, the next order of business was to install the pushrods. It is best to return the pushrods to their previously installed position in order to minimize any break-in wear. Of course, the intake side of A4 gets a new pushrod (and lifter) so in that case, it cannot be helped.

As long as you can keep the rocker assemblies together and label which is A and B, they can only go on one way because there's a feature machined into one end of each shaft that matches up with a roll pin in each head casting.
The lower intake gaskets get a bit of RTV around the coolant connections. This is pressurised, whereas the intake runners are merely under a mild vacuum. If you RTV the whole thing, good luck trying to remove it next time.

June 8, 2010
9:00 AM

With the lower intake and ignition coil in place, the upper intake is next. It is attached by only one long bolt and sealed with a simple paper gasket. Upper radiator hose and thermostat are installed in the foreground.

Note: do not forget to attach the hot water pipe to the underside of the lower intake prior to torqueing it in place. Otherwise you will have to remove the entire mess and start over. (Just like I did this morning.)

With the upper intake/carburetor assembly in place, there are a myriad of connections to make: fuel lines, ignition coil, "stove pipes" for the choke thermocoil, float drains...

and throttle linkage.

We're closing in on engine completion: need to finish torquing the exhaust manifolds and install the belt driven accessories (steering pump, a/c and generator).

Things are progressing nicely, no? This is a "before" photograph from mid-December.

2:15 PM

Rick asked me to give him a hand once again on his Derby Bentley engine rebuild. He decided to have the pistons balanced. He and I spent the afternoon installing them and torquing the rod bolts to a stretch of 0.005-0.007.

You need to achieve the requisite amount of bolt stretch while simulataneously lining up the castellated nut with the hole in the bolt so a cotter pin will slip through. Rotating the nut one-sixth of a turn (one flat) stretches the bolt about 0.0075 in, which is far greater than the allowable tolerance. Therefore, if the hole does not line up you need to grind a few thou. off of the underside of the nut to make work. Rick has a very nice grinder for this purpose.

June 10, 2010

Today I installed the power steering pump, the generator and with Dave H.'s help, the air conditioning compressor.

Also hooked up a few electrical items: coil, choke, coolant temperature sensor.

A pair of small gaskets is due in from Albers tomorrow afternoon. With those installed, the system will hold coolant.

June 11, 2010

Only had about 1-1/2 hrs. to spend on the car today. The power steering and generator/air conditioning belts are now installed and I tightened the air conditioning compressor connections. Assuming the coolant gaskets arrive today, Monday will be engine start day.

June 14, 2010

The gaskets arrived as planned. The basic head castings are the same for both banks. However, they are built up differently. The small blanking plate is attached with a gasket to the front of the B-bank. The pipe and flange attaches to the back of the A-bank on the same casting feature and supplies coolant to the heater matrix.

These are a Royal pain to install in situ. I would not recommend it.

June 15, 2010

Torquing the exhaust manifolds went swimmingly until I got to this last stud. It pulled right out of the casting. You will recall that Crewe V8's are Helicoiled at the factory. The original Helicoil failed. Mike and Ed picked up a 5/16-24 UNF Helicoil kit for me at Ypsi Auto Value but unfortunately the manifold will have to come back off to do the work.

I pressed ahead anyway and added water to the radiator. Yes, water, in case something leaks I won't have antifreeze all over the place.

I also tested the fuel system for leaks. There was one at the union at the back of the A-bank cylinder head but only because I failed to tighten it.

Hooked up the battery, turned the key. She started instantly without leaks of any kind!

Measuring surface temps at each exhaust port on the exhaust manifolds, it is clear that the engine is firing on all eight cylinders. One noisy lifter made its presence known on B-bank, but quieted down after running for a few minutes with 3/4-qt of ATF added to the sump.

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