Hey everyone,
so I am in the process of swapping my injectors for some small hybrids and was going to replace the cups with RIffRaff’s stainless cups.

I drained the coolant from the radiator, but am not able to get the drivers side block plug out, and now it’s rounded off.

my question is: Am I able to still replace the cups, and then evacuate all the coolant that would drain and oil from the cylinders after the 620 loctite has set for 12 hours?

I would use a transfer pump and then turn over by hand before trying to start.

Would this affect anything? or should I go pick up an easy out?

thanks in advance ,
John

 

Make sure you prep the ss cups first or it will not turn out well. They need a special cleaner and prep before the sealer goes on and they go in

 

what prep and cleaner do they need? There isn’t anything Different on the riffraff instructions I believe. I’m not saying I am right either

 

I'd focus on getting the block plugs out. You'll thank yourself later.

 

This is a screenshot of info from a reliable source

 

I think the information referenced is carry over from threadlocker and not applicable to the sealing compound.

"When assembling metal parts with inactive surfaces, LOCTITE® primers are recommended to ensure proper performance of LOCTITE® threadlockers."

I agree with cleaning brass or stainless cups with brake clean or similar to remove any oils that may be present. Let's remember stainless cups are not new. International uses stainless cups and stainless injector crush washers on the big six cylinders.

 

I may order the primer and degrease with acetone or brake clean. I don’t want to give them any reason to leak. I can’t imagine anything negative happening from using the primer other than having to wait for it to get here.

 

do you know what the difference between SF 7649 and regular 7649 is ?

 

Should be the same product from what I can see.

 

LOCTITE SF 7649 Primer

Known as LOCTITE 7649

https://www.henkel-adhesives.com/us/en/product/industrial-adhesives/loctite_sf_7649.html

 

During our lengthy research and development, we discovered that primer is not required for a full strength install of our stainless-steel cups for the 7.3L platform.
While primer does accelerate the cure time of the retaining compound, it is only REQUIRED if BOTH metal surfaces are an inactive metal per Loctite.
Since the engine block is cast iron it is an active metal and the stainless cups are an inactive metal we are bonding an active metal to an inactive metal which does not require a primer.

From Loctite’s User Guide:
“On two inactive metals a primer is needed to cure Loctite Retaining Compounds. If only one inactive metal, no primer is needed”.

Surface prep is very important for retaining compound. Using the Loctite primer with our cups will accelerate the cure time but does not displace the need for a clean surface area.
If you are installing new cups, please carefully clean all the bonding surfaces to avoid any contamination in the retaining compound. Also clean all bonding surfaces with a cleaner/degreaser that does not leave a residue. The Loctite SF 7649 aerosol can be a good option for a cleaner but certainly isn’t the only options out there as a good thinner does great as well.

 

Good info. Thanks for clearing that up. Sorry I posted less then accurate information

 

But you kept the conversation going and fortunately we have a very active forum, with industry suppliers as contributors.

This helps us all.

I learn stuff here almost every day

 

No problem, it isn't a competition, it is about getting good info out there and that is what is great about this forum. Easy to have good conversations where everyone is open to learning and exploring together.

 

So...what's the decision on those block plugs?