Eaton Balancing

It’s simply amazing how many times the rear crankshaft seal gets blamed for an oil leak when there are so many other places at the back of the block that can either be the root cause or at least a contributor. The rear oil seal retainer on the Y-Block is just one of these items that more often than not gets overlooked when it comes time to address an oil leak at the rear of the engine.

 

 

Upon tearing down a 292 Y engine for a rebuild, it was noted that the back of the block and oil pan were extremely oily but not much more was thought about it at the time as oil leaks on these engines seem to be common place by the time a rebuild is needed. Upon pulling the rear seal retainer loose from the block, it became apparent that the retainer itself was the source of an oil leak and had been abused somewhere in its distant past. In this particular instance, both of the grooves in the rear oil seal retainer where the side seals slip in place were distorted enough that the side seals themselves were not adequately up to the job for which they were designed.

 

 Two different thoughts come to mind on how these grooves became warped. The first one is that the grooves had become distorted when someone had tried to drive the replacement side seals in place with a considerable amount of force. The older style of asbestos seal was being used in this case and are potentially hard enough to actually exert this kind of force on the soft metal of the seal retainer. The other thought (and much more likely) is that the rear seal retainer had been pried out of the block sideways instead of being simply being lifted straight up and/or raised as would be normally recommended.

For this particular rebuild, I simply replaced the rear seal retainer with a visibly ‘good’ one and went on.  But if I had been in a bind and needed this particular retainer, then it could have very likely been straightened with some gentle persuasion using a hammer and reused.  Point here is that without being straightened, the retainer would have undoubtedly just leaked again and would have to be addressed again in the near future.

When working on these engines there just seems to be no end in the number of things that can go awry and just when you think you’ve got it all figured out, something else comes along.  The warped side grooves in the rear seal retainer just gets added to the growing list of things to watch out for.

 

 

 

 

Until next time, Ted Eaton.

Originally published in the Y-Block Magazine, Nov-Dec 2008 Issue #89, Vol 15, No. 5

In attempting to squeeze out that last bit of potential output from the Ford Y-Block (and other engines), there are those items that can be applied that may not be immediately measurable but they will be done because they will not be detrimental to the power output.  One of these items is spark plug indexing which tends to vary in its benefit depending upon the application it is being applied.  Indexing the spark plugs simply insures that the spark plug ground electrode is in a specific orientation within the cylinder to promote a more beneficial flame front when the fuel is ignited.  In those cases where detonation is a risk, spark plug indexing is of a proven benefit in that the flame front will not be split by a worst case scenario of the spark plug electrode being in a position to divide the flame path.  Indexing also allows the ground electrode or strap to be intentionally positioned away from the higher heat areas it would be subjected to if randomly placed closer to the piston and/or exhaust valve which can increase the propensity for pre-ignition.  In a normal situation where a set of spark plugs are randomly installed, the spark plug straps end up running at a variety of temperatures simply from the random placements of the straps.  In this case, indexing would provide a more accurate visual means towards optimizing jetting and ignition timing by eliminating potential variances in the spark plug readings themselves.  And if running a domed piston that’s marginally close to the spark plug, then indexing also helps in preventing the ground electrode from contacting the piston and potentially closing the gap.

 Because both the spark plug threads in the Y heads and the threads on the spark plugs themselves are randomly machined in relation to the ground electrode attachment, the spark plug strap orientation will also randomly install in a myriad of positions within the combustion chamber.  To install a sparkplug so that its ground electrode is in a specific position within the combustion chamber will require trying several spark plugs in a given hole until the desired orientation is achieved.  If the heads are off the engine, it’s simply a matter of observing the electrode position and trying different spark plugs in a particular hole until the electrode resides in the desired position when tightened (see Figs. 1&2).  If the heads are on the engine, then the spark plug porcelain can be marked with a magic marker stripe that aligns with the ground strap where it attaches to the base of the spark plug.  This spark plug is then installed and tightened in the various spark plug holes until the stripe or mark falls into the desired position (see fig. 3).  This process is continued until all the cylinders have an indexed spark plug specific to each cylinder.

 

It will not be unusual to use more than a full set of spark plugs in order to have enough to properly index all eight cylinders.  The spark plugs that will not index or align for a given set of heads can potentially work on another set of heads though so just label those as not fitting a specific set of heads so they are not re-ran through the same process at a later date on the same set of heads.

 

So just where is the optimum orientation of the electrode?.  For the Ford Y-Block, the electrode ground strap will be at the highest position in the combustion chamber where the center tip is fully exposed to the oncoming piston and the compressing fuel mixture.  If taken one step further, then the electrode strap will be angled slightly towards the intake valve so that the strap is intentionally placed further from the exhaust valve (see Figs. 1,2&3).  This promotes some additional cooling of the spark plug strap as the intake charge enters the cylinder while also keeping the strap itself again cooler by not being as close to the exhaust flow leaving the engine.  The opposing thought process to this is to angle the electrode attachment towards the exhaust valve to promote some additional intake air flow.  Regardless on what you decide for the final placement, just be consistent in the methodology or thought process that you use.

 

It ends up being quite an effort to go through the process of installing that first set of indexed spark plugs.  But there is a way to capture this information so that future changes of spark plugs can be made and properly indexed without having to go through the process of checking each spark plug in each respective spark plug hole again.  All that’s needed now is a fixture that the indexed spark plug from each cylinder can be installed in and the location of each ground strap attachment position is recorded on to indicate the cylinder for which it belongs.  What has been found to be expedient and not requiring a lot of fabrication is to simply use a spark plug anti-fouler (Fig. 4) as the basis for a tool to accomplish this.  In order to make this work, each indexed spark plug is removed from its respective cylinder in the heads, installed in the anti-fouler, and the location where the ground strap or electrode is attached to the spark plugs base is marked and recorded on the side of the anti-fouler.  Personal preference is to use a metal engraver to insure the marks are permanent.  To make it easier to see the spark plug’s ground strap, the hole in the bottom of the anti-fouler is made larger (Fig. 5 & 7).  The next time a set of spark plugs is needed, the new plugs are simply screwed into the ‘tool’ and by viewing the ground strap attachment, the ‘best fit’ cylinder number marked on the tools side will indicate exactly which cylinder will get that particular spark plug.  If the ground strap aligns perfectly with the mark, then you’ve got an exact fit.  Again, you’ll likely need more than eight spark plugs to make a ‘perfect’ set for your Y engine. When the tool has outlived the set of heads it was originally marked for, it can be simply remachined to give a new surface on which to mark a new set of spark plug locations.

 

Another ‘tool’ option is to simply take a flat piece of material and drill and tap it to accommodate a spark plug being screwed into it (Figs. 8,9,10).  The spark plugs that have already been indexed within a given pair of heads can then be removed one at a time from their respective cylinders, installed in this new tool, and the electrode strap locations marked on the tool as to the cylinder that particular spark plug belongs.  Like with using the anti-fouler, any new spark plugs can then be installed in this tool and you will know immediately for which cylinders the new spark plugs will be suitable for.

 

Now that you’ve made a tool to assist in indexing the spark plugs without having to actually install them in the heads, it becomes important to mark the heads so that they can be reinstalled on the engine without unknowingly swapping sides.  Heads can be marked L or R, DRV or PAS, or any other markings as long as they are sufficiently identified so they can be installed back on their original sides or banks which in turn keeps the cylinder numbering on the tool the same.  Because the Y heads are already left and right specific by lieu of the temperature sending unit and the blocked water ports at the back of the heads, not doing the labeling or marking is not a show stopper on a Y engine but can be a big consideration if doing this on other engine designs.  If the heads have been inadvertently swapped, the tool no longer works as originally labeled.  If you are indexing spark plugs for several engines, then mark the tool (or anti-fouler) as to the engine or the heads for which the tool belongs (Fig. 11).    Until next time, Ted Eaton

 Originally published in the Y-Block Magazine, May-June 2008 issue, Issue #86, Vol 15, No.3

Included on that list of old racers tuning tricks is spark plug side gapping.  What’s being discussed here is not a true side gapped spark plug but a gapping procedure or electrode modification that allows the spark to actually fire off of the very edge or ‘side’ of the spark plug’s ground electrode.  In lieu of a better description, this gapping process will simply continue to be called ‘side gapping’.  Side gapping is performed even though the end result may not be measurable but a logical thought process will maintain that doing this will not be detrimental to efficiency or performance and in fact, should help it.

 

Like spark plug indexing, spark plug side gapping will vary in its benefit depending upon the application to which it is being applied.  While this procedure tends to be very effective on two stroke engines, the benefit on four stroke engines is less predictable depending in part to the combustion chamber design and air flow characteristics of the engine in question.  On both the two and four stroke engines, the immediate benefit is typically observed in engine starting where it’s quicker or with much less starter effort.  The general premise behind side gapping lies in getting the spark to fire directly on the end of the grounding electrode instead of having the spark shrouded by the electrode strap.  Doing this is typically done in conjunction with spark plug indexing in order to get as much exposure of the spark to the compressed fuel mixture as possible.

 

A typical out of the box spark plug will have the ground electrode (strap) completely covering the center post consequently shrouding or covering it to some degree.  Side gapping will simply modify this strap so the end of it is exactly in line with the centerline of the spark plug thereby putting the spark in a position to fire directly on the end of the ground electrode which in turn permits the spark to be better exposed for igniting the fuel mixture.  A variety of methods can be employed to shorten or remove the excess amount of ground electrode strap so that the new end is centered directly over the center electrode.  A grinder or file are equally effective but in either case, care must be taken to insure that the center electrode (tip) or other portions of the spark plug are not unduly damaged or altered in the process of working on the ground strap.  After the strap is appropriately modified, it will need to be deburred and then the gap reset to the desired specification.  It’s important to note that the bottom edge of the electrode where it has been shortened does need to keep a sharp edge and not be rounded in order to promote a more decisive and consistent length spark.      

 

Spark plug side gapping is just one more tuning aid that when used with the myriad of other seemingly unimportant tuning tools accumulatively adds to a measurable increase in power output that by itself would not be significant.  More simply said… “every little bit helps”.

 

Until next time, Ted Eaton

 Originally published in the Y-Block Magazine, Sept-Oct 2008 issue, Issue #88, Vol 15, No.5