fatalbert1

Quick question. I am doing the timing belt replacement on a 1998 ls400 as well as the other necessary parts. I did this before about nine years ago, the only part I remember is I didn't want to do it again. There is oil leaking below the crank shaft from the weep hole. I have most every thing off except the Crank shaft pulley and the cover behind it. I am hoping that the leak is behind the crank pulley to avoid doing the cam shaft seals. I have the factory manual.

My question while I am taking a break is why do you need to remove the radiator completly? I have the fan and shroud off but have not disconnected the A/T Fluid lines yet to lift out the radiator. It looks like there is enough room to do everything without taking out the radiator. Maybe there is not enough room to get a puller in to remove the crank pulley? The manual call for removing the radiator, but I don't remember having to take it out last time. I hope to avoid the excitement of having to replace the cam seals on this model ls400.

Thanks,
Al

bradland

You might be able to get away with not removing the rad but why wouldn't you want to? The amount of room gained for a little effort is definitely worth it. Maybe you are choosing not to replace the water pump while you're in there...?

timmy0tool

iTrader: (7)

it's easy to remove and less likely to damage it, why not remove it?
unless you are not planning on replacing the water pump which is highly suggested, you should remove the radiator.

i would also at the least do the crank seal if you don't want to do the cam seals. what mileage are you at?

PureDrifter

iTrader: (10)

+3, you have to drain the coolant to swap the water pump anyway, may as well remove the empty rad to give yourself space to work.

TakaM

Like other's have posted, pulling radiator off on 98 LS400 is really easy. Working on timing belt without radiator makes it much easier and also avoid damaging the radiator fins in the process.

fatalbert1

I went ahead and pulled the radiator out. I am replacing everything - pump, idlers, belts and the crank seal. Has anyone here done the cam seals on this engine. I know you have to be careful with the variable valve mechanism and not let the cam roll back and let the valves hit a piston.

At 20 years I would guess the cam seals are rock hard by now and should be replaced, but the variable cams worry me.

I have the factory shop manual and it is pretty good if you read it carefully. Has anybody done the cam seals on this model engine and had any problems or cautions.

Thanks,
​​​​​​​Al

sha4000

iTrader: (1)

Camshaft seals replacement is not related to the TB so if they are not leaking I would leave them alone. Now if your doing valve covers gaskets and spark plug tube seals I MIGHT recommend doing the seals. I did the TB and the seals at the same time and it was nerve racking for ME at the time plus a lot of work.
​​​​​​https://www.clublexus.com/forums/ls-...ith-vvt-i.html

fatalbert1

Thanks for responding. I read your posts when you were doing the timing belt and seals. My car was leaking oil quite a bit. I have most everything pulled but I have to taken the timing belt off yet. There is so much oil I have not been able to tell for sure where it is coming from. I hope when I pull the crank pulley off that it will be obvious that it is coming from there and I will not do the cam seals.

I have been reading the factory manual overover and over and it does not have a section describing how to replace the cam seals. You have to piece the procedure together jumping around beteen the timing belt and cylinder head sections. The more I read the more I worry. I may have no choice but to do the cam seals if they are where it is leaking.

I have lots of question but one right now is one instruction in the manual on page EM-36 for installing the service bolt to the sub-gear. It reads "Boring the service bolt hole of the sub-gear upward by turning the hexagon wrench head portion of the exhaust camshaft with a wrench." Do they really mean Bring instead of Boring?

If you have a manual, could you explain what the warning means on page EM-36 with respect to keeping the camshaft level while being removed? Do they really mean loosening the bearing cap bolts in the correct sequence to keep from stressING the camshaft and bending it or cracking the head.

I think I will write myself a step by step procedure to follow if I have to do cam seals.

Thanks for your time.
​​​​​​​Al

TakaM

I did the whole timing belt/water pump/crank seal/various pulley/spark plugs/various hoses replacement project but I did not touch the cam seal since it wasn't leaking.
I was too afraid that I would mess something up and my idle "EricTheCarGuy" also mentioned that don't touch the cam seal if not leaking. Trying to replacing it may actually create the leak, hence used that as an excuse to chicken out.
If it does leak one day, I may just handed over to an independent shop (and I'm usually DIY on lot of things).

billydpowe

iTrader: (1)

use an Aisin KIT dont go cheap

Scraape

i've done the timing belt / water pump job on my 98 and just did my 99 last week.

I had to do cam seals on the 98, luckily they weren't leaking on the 99 .

Removing the radiator will certainly help you get that crank pulley off.

I followed the tutorial i found on clublexus for 98-00 1uz's, I locked the flywheel with a fat allen key and it came off with a bit of force, a jack handle helps get some leverage.

Just make sure you mark all your bolts, and make sure you have the belt lined up 100% , not a tooth off.

Refer to my build thread (in my signature ) or this thread if you end up having to do cam seals:

https://www.clublexus.com/forums/ls-...ith-vvt-i.html

fatalbert1

Believe me, I don't want to do the cam seals. I have been looking at the car and I can not say for certain where all the oil is coming from because it was slung all over atound the cam belt. If I had to bet, it looks like it is coming from the passenger side cam seal. I was hoping when I got all the covers off and the crank pulley off it would be obvious. I think I am already committed to doing the cam seals. All the parts should show up tomorrow and they are all OEM parts.

I did the timing belt and all the other stuff the last time about 90K miles ago. It wasn't that bad but there was a lot work because I also had to take the intake manifold off to fix wiring on the anti-knock sensors that a mouse got into.

I just got back from picking up two 6mm bolts needed to hold the sub-gear during the cam removal. So I guess I will forge ahead. Two shops nearby including the toyota dealer have such horrible feedback ratings I decided not to use them since this is so complex.

​​​​​​​Stay tuned.

fatalbert1

I spent today re-reading the factory service manual and the saga you posted with photos and questions. of your cam seal job. Since I only have my wife screaming for her car and I am used to that, I am taking my time to understand everything to not make a mistake. I am getting more comfortable now and marked all the torque values that are inch pounds instead of foot pounds. Don't ask how I know to do that.

I have one question for right now. The service bolt that is used to lock the sub-gear to the main gear, when you are lining this all up, does the bolt thread into both gears through threaded holes and you need to turn the exhaust cam to line up the holes. This appears to be only on the exhaust cam. I am not quite sure what this does yet. The manual is not clear on this and calls it the main gear to the sub-gear. I don't see a main gear called out on any diagram and think they mean the unlabeled gear on the exhaust cam.

Thanks,
​​​​​​​Al

Scraape

yes, you will need to turn the exhaust cam up to line it up to put the service bolt in . Accomplished with a 24mm wrench

Losiracer2

you better do the cam seals or you'll regret tearing into the engine again prematurely.

I had to do my timing belt 40k miles early since my crank seal failed and coated it in oil thanks to the cost cutting previous owner.