8BA Front & Rear Rope Seals

L

LostAtTDC

Junior Member
I have the Best Gasket GraphTite rear main seal and the standard white front rope seal.


  • I installed the rear seal and trimmed it according to the instructions. However, when I installed the crankshaft, the seal compressed and protruded beyond the block and cap surfaces. Should I trim it once again using the supplied trimming guide?


  • For the front rope seal, how long should it be soaked in oil before installation? Also, once installed, should it be trimmed using the Best Gasket trimming guide?

Thank you for any guidance you can provide.
 
Personally when I’m ready for seal installation both front and rear I have bearings in block and caps. With front pulley partially on I put front seal in oil pan. Now install oil pan with gasket. Just snug up now remove and trim using template like best. Repeat with timing cover. Now do seal in rear cap. Lastly the pain remove crank put seal in block reinstall crank snug up center and front mains. Now remove crank and trim seal. Now you’re good to go with zero leaks.
Edit ~I DONT SOAK ANY SEALS IN OIL. DRY FOR ME. I light coat of oil on crank before final assembly.
 
Last edited:
I made my own trimming guide from a piece of metal, the same thickness as the gasket. File a slot the same width as the seal, but way deeper. Use a razor blade to cut the seal. Trim the gasket before you put the seal in the grove. Use sealant at least where the gasket and rope seal meet. I use Hylomar Blue, but I believe Permatex 2 is similar. I cut the seal flush on the block side and use the guide to trim the seals on the oil pan side.
 
Last edited:
The rear GraphTite seal sticks up around .100" on both sides and the front white rope seal seems to stick out .200" on both sides. I soaked the front for about 2 hours in oil and used a socket to squish it into the cover, but it seemed to want to bounce back.
PXL_20260906_194235811.jpg
PXL_20260906_194351291.jpg
 
I didn't understand your problem.
Read posts #2 and #3.
The seals need to be trimmed. Flush on the block side and proud by the thickness of the gasket on the oil pan side.
The gasket needs to be cut back so it butts up to the seal.
 
Didn't the gasket kit come with seal installation instructions? It was a long tome ago, but the last set of Fel-Pro pan gaskets I used came with installation instructions, a trimming gauge, and even a razor knife. That engine never leaked a drop until I had to change the oil pump and remove the pan. I thought if I was careful I could get by using the old seals and gaskets, but it developed a slight seep in rear main seal afterwards. Not enough to cause me to take the whole thing apart again, but enough to require a wipe down every couple of months. I think rope seals are "one and done" thing.

I agree with the previous poster; those seals need to be trimmed.
 
69a said:
I didn't understand your problem.
Read posts #2 and #3.
The seals need to be trimmed. Flush on the block side and proud by the thickness of the gasket on the oil pan side.
The gasket needs to be cut back so it butts up to the seal.
Click to expand...

590440
 
I agree with all of the above, however I don't use any sealant in the seal slot. Both seal slots have a drain hole that prevents the seals from becoming over saturated with oil. I do put a little sealant where the gasket butts up to the rope seal. I never use regular RTV on oil pans or fuel systems. Hylomar Blue or Permatex 2.
 
I as well NEVER soak the rope seals in oil as KiWinUS wrote above. I also never shorten the front rope seals that come in the current Best brand gasket sets.

For the front rope I simply place them in the front cover and oil pan than I use a round dowl to roll the seals down into each grove. I add pressure as i roll the dowl the length of each front seal. Then I trim the oil pan gasket so it sits around the edges of the seal. A small amount of sealer if the final step only placed around the edge of the rope seal.

The rear graphite seal I place in each grove and once again use the dowl to roll the seals into the groves pressing as I go along the diameters just as I did for the front seal. The rear seal edges that stick out I now trim using the supplied template spacer. The rear area of the oil pan gasket I trim around the outer edge of the rear rope same as above.
Final step a small amount of sealer is added only around the outer surface areas of the rear rope as well.
This works extremely well.
Ronnieroadster
 
Ronnieroadster said:
I as well NEVER soak the rope seals in oil as KiWinUS wrote above. I also never shorten the front rope seals that come in the current Best brand gasket sets.

For the front rope I simply place them in the front cover and oil pan than I use a round dowl to roll the seals down into each grove. I add pressure as i roll the dowl the length of each front seal. Then I trim the oil pan gasket so it sits around the edges of the seal. A small amount of sealer if the final step only placed around the edge of the rope seal.

The rear graphite seal I place in each grove and once again use the dowl to roll the seals into the groves pressing as I go along the diameters just as I did for the front seal. The rear seal edges that stick out I now trim using the supplied template spacer. The rear area of the oil pan gasket I trim around the outer edge of the rear rope same as above.
Final step a small amount of sealer is added only around the outer surface areas of the rear rope as well.
This works extremely well.
Ronnieroadster
Click to expand...

Once rolled in, do the front seals sit flush? Mine seem to stick out about .200" after rolling them in, with the crank in the block, and the front cover installed.

Also why not soak the white front seals? I was told by BestGasket the white seals are made like the original and the original shop manual should be followed which states 1 hour soak in oil.
 
You need to trim the seals. It doesn't matter whose method you use, at the end of the day you need all the surfaces to meet flush. The rope seals need to encompass 360 degrees and their two ends must be cut so they sit together flat and square. All this is done allowing for the thickness of the gasket. The gasket also needs to be trimmed so that it sits snug against the outside diameter of the seal. The gasket doesn't go between the rope ends. Glenns attachment in post #8 says to have up to 0.015" crush on the ropes. Kiwi's method ensures the rope is sitting at the correct height.
I've had no trouble cutting them flush on the block for the rear and flush on the timing cover for the front.
On the oil pan side you need to allow for the thickness of the oil pan gasket. Maybe plus a fraction.
Don't over tighten the pan.
 
LostAtTDC said:
Once rolled in, do the front seals sit flush? Mine seem to stick out about .200" after rolling them in, with the crank in the block, and the front cover installed.

Also why not soak the white front seals? I was told by BestGasket the white seals are made like the original and the original shop manual should be followed which states 1 hour soak in oil.
Click to expand...

Seal should be slightly proud around the circumference with .200" being way to high like the picture below. Make sure you roll the seal into the groove with pressure. Start in the middle and work toward the ends.

BestGasket white and black are Teflon and/or graphite so they slip into the groove so there is no need to soak them in oil. The originals, made of asbestos required an oil soak.

590470
 
Last edited:
RE: the picture above. I always thought the "popsicle stick" supplied with the gasket kits was a guide get the amount proud of the surface correct. What is that picture showing?
 
There’s a gasket material template come with Best set and the stick is to save your finger from razor knife. Both also supplied in kit.
 
LostAtTDC said:
Once rolled in, do the front seals sit flush? Mine seem to stick out about .200" after rolling them in, with the crank in the block, and the front cover installed.

Also why not soak the white front seals? I was told by BestGasket the white seals are made like the original and the original shop manual should be followed which states 1 hour soak in oil.
Click to expand...

The front rope I never cut shorter than the length they come. Which is the same length Ford made them.

As to soaking the rope I don't do it never have and after a couple of hundred flathead engine builds I continue to do it this way. Only oil I use is on the rope surface is the area that contacts the seal ring.

Soak the rope if that's what you want to do.
Ronnieroadster
 
You must log in or register to reply here.
Back
Top