1998 V70 Timing belt, cylinder head work 330k miles!

5rivers · Post by **5rivers** » 03 May 2016, 06:08

Greetings!!
I have re-assembled all the parts I extracted from the engine compartment to replace the valves, valve stems, timing belt, etc...
And now am about to fill the coolant system and add oil. I am wondering if after a few hundred miles I should replace the coolant and/or the oil? I had filled the coolant system last summer when I thought I was done (ha!) and had to drain that out when I discovered a coolant leak at the head gasket (then had to start all over!). Appreciate your recommendations!

Post by **rspi** » 03 May 2016, 08:07

I usually flush the coolant system with 4 gallons of distilled water, then I add the G-05 coolant.

I usually add fresh dyno oil, run for 5 minutes, change with dyno, drive 50 to 100 miles, then change again with filter. Sometimes I change 1 last time at 1000 miles.

However, if you didn't heed Erik & Dosdrick's suggestions about having a machine shop mill the head, I would keep the receipts on the oil and filter.

5rivers · Post by **5rivers** » 18 May 2016, 20:57

Greetings again!
I was able to jump start the V70 and it started, but the RPMs just keep going up and up and up. Once the needle hit 4000 RPMs I turned the car off. I started it again and the tachometer needle did the same thing - raced upward! I suspect I need to adjust the throttle as the motor is not idling down to 900 RPMs. Any other thoughts on what could cause this condition? Appreciate all your recommendations!

Post by **abscate** » 18 May 2016, 22:16

Is the throttle body valve completely closed? I don't know the pre 99 stuff that well, so let the experts chime in.

5rivers · Post by **5rivers** » 29 May 2016, 14:04

In order to determine if the throttle body valve is closed I need to remove the accordion-type hose from the throttle opening to the air box. Is it okay to have it removed and start the car to see if the valve is closed? Would a TPS (throttle position sensor) cause this type of acceleration? I did loosen the throttle cable a bit but had to tighten it up so the cable would not move off the take-up wheel it is attached to (the connecting steel bar with the little cups on each end attaches to this wire-holding wheel and the other end is attached to the throttle body). Once I did loosen the throttle cable, the car started, I pulled on the cable to increase the acceleration, but then the car sputtered and died/shut off. Not really sure what to do next. Appreciate any suggestions!

Post by **j-dawg** » 29 May 2016, 14:21

Yes, it's okay to remove that hose. The hose is upstream of the air filter.

5rivers · Post by **5rivers** » 30 May 2016, 07:03

Greetings!
I lessened the tension on the spring that is part of the throttle valve connection. That seemed to eliminate the rapid acceleration of the motor and then tightened the tension on the throttle cable, again so it would not move off the take-up wheel the cable winds around. Then I reinstalled the large hose that connects the throttle body opening to the air box. Had to give the gas pedal a little push to keep the motor running. The motor ran rough and I noticed a lot of air coming from under the vacuum tree. There is a solid hose connection that is part of the intake manifold under the vacuum tree that points downward that is missing a hose. I am not sure where the other end of the hose is supposed to connect, but will look at some of the photos in this diatribe on my cylinder rebuild. Of course, I appreciate any input on this as I scan this topic and the databases on this site.

Post by **MadeInJapan** » 30 May 2016, 07:30

Does that hose not connect to the PCV system? It should like that coming loose is causing all kinds of issues. Another thing that happens is a smaller hose can get pinched. A lot of smoke up from below the tree sounds like the manifold is leaking- Sorry I have not read the entire thread. Did you replace the gasket in there?

Post by **erikv11** » 30 May 2016, 09:25

This sounds like the big thick hose for the brake booster. Check this out https://www.matthewsvolvosite.com/forums ... =1&t=65002, in that post it is called "line 7."

Post by **MadeInJapan** » 30 May 2016, 09:43

Yes, erikv11!! - He would have obvious braking issues if that were the case...but unable to drive it- it might be difficult to test...Still could put the key in position II and punch on the brake and see what gives...it's a huge hose that connects to the base of the vacuum tree so it should be in plain view if you take the throttle cover off. It can get brittle like so many other rubber hoses in these cars- esp. if it's set for awhile. Oh, and any opening to the vacuum system whether it's one of the small hoses or the larger brake booster hose would allow unmetered air in and cause the "sputter and die" syndrome so it's a great observation for sure!

1998 V70 Timing belt, cylinder head work 330k miles!

Re: 1998 V70 Timing belt, cylinder head work 330k miles!