BAC Forum

General Boards => Technical Support => Topic started by: Bob Reeves on September 16, 2021, 06:33:44 PM

Title: Gas Strut on Engine Hatch
Post by: Bob Reeves on September 16, 2021, 06:33:44 PM
I replaced one gas strut on the engine hatch of my 07 Patriot Thunder.  They say you should replace both at the same time, but I did only one.  Not an easy job, or at least wasn't the way I did it.  The hatch is now very hard to close.  I got the exact replacement strut, 140 Lb.  Do these struts  get a little easier to compress with use? 
Title: Re: Gas Strut on Engine Hatch
Post by: Joel Ashley on September 16, 2021, 11:09:57 PM
Sometimes retailers’ cross-reference suggestions aren’t accurate, often because the original model # is defunct.  140 seems high.  Our hatch is relatively light, and it’s hard to imagine two struts of that rating being necessary to hold it open.

Another forum’s discussion of similar topic implied the original engine hatch was 85# and was weak.  The poster thought another owner’s 150# was too much, and thought 120# would be appropriate, suggesting this site:   “Future Sales provide PN: ML-37-120 (8677QX) struts”.  But it’s a 2 year old thread and I didn’t find that strut there. I saw it elsewhere, including e-bay:  https://www.ebay.com/itm/383303178702  .  It doesn’t mean it’s the one you require.

Length must be correct or installation would prove difficult, which may have been your issue, Bob.  I’ve only replaced struts on our SUV, rear hatch and hood, and it wasn’t hard.  Consider this one, but otherwise peruse for the right lengths, extended and compressed:  https://www.futuresalesrv.com//index.php?route=product/product&path=61_73&product_id=61&mfp=3f-filter-by-pound-force%5B34%5D

Joel
Title: Re: Gas Strut on Engine Hatch
Post by: Stan Simpson on September 17, 2021, 01:56:08 AM
I recently replaced my engine compartment struts. Here is what I replaced them with.


Gas Spring SBD-GSNI-5250-30 or LGP6-185-30 Strut Prop Rod RV Camper Hatch

From: R & P Carriages - robin@needatrailer.com - tel:(815) 357-3292

$44.00 for the pair, including shipping

Work perfectly.
Title: Re: Gas Strut on Engine Hatch
Post by: Bob Reeves on September 17, 2021, 02:15:59 AM
Stabilus Lift-0-mat  752991.  $25 plus shipping.   Identical to the "good" one.  same length and 140 lb.  I had to remove the Rubber headed bolts that act as bumpers when hatch is down.  I had to do this to allow the hatch to be raised high enough so that the strut would match the distance between the holding posts.
Title: Re: Gas Strut on Engine Hatch
Post by: Stan Simpson on September 17, 2021, 03:09:38 PM
I'm really skeptical about that "140 lb" strut. I have 2 60 lb struts on my street side bays that come out with the living room slide, and they are a chore to get down. Of course the travel is longer, and the doors are bigger. Just seems odd to me. My engine compartment struts are 30 lb.
Title: Re: Gas Strut on Engine Hatch
Post by: Fred Brooks on September 17, 2021, 07:27:30 PM
  If someone would post a picture of the engine compartment door in question, I would appreciate it. Thanks, Fred
Title: Re: Gas Strut on Engine Hatch
Post by: Eric Maclean Co-Admin on September 18, 2021, 02:47:51 PM
Bob
A word of caution if you use too heavy of gas strut for the application you risk breaking the attachment points ( ball or brackets)

Years back I had an older RV tech I worked with show me a trick to determine strut size ( lbs if lift)

Here's the way he showed me how to determine if the strut you need .
1) remove both struts
2) cut your self a piece of wood 2x2 or there abouts the correct size to reach from the lift strut attachment point to the ground while the door is at right angles to the coach
3) now place your wooden support on a common bath room scales and read the weight in lbs.
4) take that reading and add 10 % and then divide by the number of struts.

This will only get you the number for the lift in lbs you still have to know the max length and compressed length for the strut
But I have used this method a couple of times to determine wheather the strut installed had just gone bad or wheather it ever had enough lift power to do the job.
With the cheaper coaches the bay doors are often foam filled and can get water logged making them heavier to the point the factory strut won't lift them in this case you can use the same technic to compare two doors on the same coach for there individual lift requirements to determine if the door in question is indeed water logged.

Hope this helps
Eric
Title: Re: Gas Strut on Engine Hatch
Post by: Bob Reeves on September 18, 2021, 09:44:35 PM
The strut that worked had the following on it,                            The Data sheet that I was able to find had the following
Lift-O-Mat                                                                               Product Category           Gas Spring
High Pressure                                                                          Stroke                           9.84 inch (250 mm)
Do Not Open      Do Not Heat                                                    Compressed length       13.19 inch (335 mm)
Mexico  Razos  Arizpe   Coah  75908                                          Extended length           23.03 inch (585 mm)
752991  0600N   313/06  A  2                                                   Maximum Force             135 lbs. (61.17 Kg)
                                                                                              Dampening Method         Gas
I ordered the same part number (752991)  Have measured the old one and it corresponded to the data sheet.  The new one checks out on the the dimensions as best as i can determine.  Cannot manually compress the strut.

I have taken some pictures with my phone.  Trying to figure out how to post them here.  Suggestions would be appreciated.
Title: Re: Gas Strut on Engine Hatch
Post by: Joel Ashley on September 18, 2021, 11:33:07 PM
Bob, I’m not one to use my phone for such pix, preferring a regular camera or iPad, but perhaps our instructions for posting photos will be helpful.  Go to the “Home” tab menu (above left) and scroll down to select Forum Assistance, then “Adding Images & Graphics to Your Post”.  You must be signed in to get to it.

Aside from that, I use and recommend an app called “Image Compress and Resize Easily” by DKit, Inc. from the Apple App Store.  I don’t find it at Google Play Store, but if your phone is Android you may find another useful compression app there by searching Image Compress.  My app easily shrinks a photo to under the 300kb Forum limit. 

You need to use the regular “reply” button at the bottom right of the last post.  If you use the “Quick Reply” button at the bottom left, it provides no feature for adding images.  If you haven’t already, you’ll need to spend a little time experimenting with both a compression app and the Forum posting feature.  But except for some apps that are too complex and that I personally wouldn’t choose, it’s not rocket science.  You should find your way around and figure out things in no time.  A little practice always helps, too.

Joel