I am getting considerable vibration from my 98 Accord EX 2.3L AT. It is in every gear from P to D. Not changing or different unless the rpms go up. Then it smooths out. I have tested the vacuum on the rear motor mount and it does hold vacuum and the solenoid is sucking through it off the manifold vacuum. Not sure what else to account for other than just collectively tired mounts. The vibration does NOT change when pulling a vac on the rear mount. I was questioning maybe a TC issue for a second since the transmission has had a delayed 1/2 shift when cold for the last 50k miles. Thought maybe something was getting worse in that respect but since it does not vary from P to D I am leaning towards mounts unless someone has a better suggestion. My question other than that though is has anyone used the ROCA motor mounts. I found a set on ebay for about $200/set and wanted to know if they truly exceed OEM specs or are they just another junk off brand. Otherwise I will just go Honda but was trying to save some money. Here is an ebay item number to what I am looking at. Ebay item #: 180979217611. Thanks.

 

In my experience, you can visually detect damage in the mounts. Here's procedure, which requires care and a trusted partner (wive's are good at this!).

1) Place car in park and set e-brake firmly.

2) W/ foot also on brake, place car in R to observe rear mount movement.

3) Quick throttle blips to 2000-2500 rpm. Observer stands to pax side looking behind engine w/ intake duct removed. A flash light is necessary. Look for excess movement and torn rubber parts. I found the rear mount torn and moving 1-2 inches.

Forward mount can be inspected directly w/o engine running. Look for broken spokes of the mount.

Side mounts can also be visually inspected. Hoever, I've never seen any damage in these, but it may occur.

Regarding the vacuum-modulated mount, I've never been able to detect any difference between actuated and non-actuated vibration at idle.

I've bought used mounts to use since I read somewhere that aftermarket mounts are too firm and result in more vibration.

There is a specific mount tightening procedure in the engine installation section. It may have more to do w/ engine installation than mount adjustment, but it's there.

good luck

 

Can't tell you anything about that ebay set, but if there's no change when you apply vacuum that suggests the rear mount is broken. Usually it won't hold vacuum, but maybe there's some strange kind of failure where it holds vacuum but still doesn't work properly?

Can't argue with Tex about not being able to feel the difference, since I haven't actually done this myself.

I've also seen the sequence for tightening the mounts. Seems like that would have to be related to how each of the mounts share the load. That in turn should affect the vibration. I did have to do that when changing the timing belt in our 1998, but I don't have that car or the shop manual any more.

 

I have in the past replaced ones visually broke but none of these are in that regard. Just thinkn mayb they are collectively much weaker being 16yrs old. Mayb replace them and make sure i do it in the right order?

 

Looking at the engine is it smooth or not as in an engine miss?

 

No. No miss. Very smooth that way. Heck u just raise the rpm of the engine to 900/1000 it is smoothed out. You just can't keep it there.

 

Did the vibration develop after timing belt maintenance? It is possible to get balance shafts misaligned which would increase vibration.

What is idle speed? Have you gone through idle adjustment process?

good luck

 

I hav seen things on the balancer shaft. It has vibrated for a while. Seemingly worse lately but more consistent. Used to b better in warmer weather. Now its just always. Idle is dead on 800. My grandmother had timing belt done at 55k in 08ish. Maybe they got balancer off? How hard is that to adjust? Is that a whole redo of timing belt? If thats the case might just wait it out a bit. Cars only at 99k now.

 

Checking balance shaft alignment does require removal of PS pump, accessory belts, valve cover, L side motor mount, lower timing belt cover, and crankshaft pulley.

W/ crankshaft at TDC, check balance shafts for alignment; Forward balance shaft pointer on sprocket aligned w/ marker on engine cover behind sprocket, and rear balance shaft dimple aligned w/ reinforcement intersection on cover behind sprocket at about 5:00 position. See attached pdf.

It may be possible to do the above job w/ reduced effort. Here is what you may be able to do:
1) remove upper timing belt cover (valve cover must be lifted to release)
2) Align crankshaft pulley to TDC (red mark aligned w/ pointer
3) Inspect forward balance shaft position w/ good light. You may be able to see sprocket pointer align w/ TDC mark on cover behind sprocke
4) Attempt to insert a 1/4" or 6mm bolt (100 mm or 4" length) into the rear balance shaft lock opening. It should go in fully and hit opposite side of shaft tunnel, about 2.9 inches penetration.

If both above checks work, I would be fairly confident balance shafts are aligned.

good luck

 

Cool. I will have to check that when it warms up. Havta see if alldata has any pics tho. Im better w pics. Lol