DO NOT LET FUEL TOUCH THE SEALANT YOU APPLIED UNTIL IT IS TACK-FREE FOR 2 HOURS MINIMUM. WHEN YOU USE PROSEAL 860, DO NOT USE A PRECOAT. PROSEAL 860 IS RECOMMENDED FOR SMALL REPAIRS ONLY, DUE TO ITS SHORT APPLICATION TIME.
USED TO REPAIR FILLET SEALS OF BMS 5-26 WHICH ARE IN A FULLY CURED CONDITION. AVAILABLE IN
6 OUNCE SEMKITS ONLY FROM PRODUCTS RESEARCH AND CHEMICAL CORPORATION, GLENDALE, CA. COMES WITH A SPECIAL PRIMER. USE WITH ADHESION PROMOTER.
Sealant Usable Time
Figure 804

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MAINTENANCE MANUAL

 (b)  
Examine the seal area to make sure you have the correct selection of tools for the task.

 (c)  
Apply a thin layer (precoat) of correctly accelerated BMS 5-26 Type II Class A-2 sealant to the surface with a stiff bristled brush (Fig. 805). 1) Make sure you apply precoat into all crevices and the full

 length of the area that you will apply sealant to. 2) Apply the precoat at a width of 1/2 inch on each side of seams. 3) Make sure the precoat is applied smoothly.
 NOTE: If you let the precoat fully cure, clean with
____ solvent, Series 93 (AMM 20-30-93/201) before you apply the fillet seal. It is not necessary to let the precoat cure unless the precoat and the sealant you use for a fillet seal are from different manufacturer product lines. For example, do not use a precoat of BMS 5-26, Type II, Class A-2 with a fillet seal of PR-1826.
 CAUTION: MAKE SURE YOU APPLY THE FILLET SEAL CAREFULLY TO PREVENT
_______ AIR BUBBLES IN THE SEALANT. THE FILLET SEAL WILL NOT BOND CORRECTLY IF THERE ARE AIR BUBBLES IN THE SEALANT.
 (d)  
Apply a small fillet seal of BMS 5-26 Type II Class B or other approved sealant with the sealing gun (Fig. 806). 1) When you use a nozzle tip, point the nozzle tip into the

 seam, almost perpendicular to the direction of travel. Keep a bead of solvent in front of the nozzle tip.

 (e)  
Use a sealant fairing tool and push the first fillet seals tightly into position (Fig. 807). 1) Apply all the first fillet seals. 2) Make sure all sealant fairing tools are clean. 3) Do not use solutions or lubricants to help the fairing

 tools move over the sealant. 4) Clean the fairing tools frequently with clean gauze.

 (f)  
Apply BMS 5-26 Type II Class B or other approved sealant a second time to make a full bodied fillet seal.

 NOTE: A larger nozzle than was used for the first fillet seal
　
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